FORUM REPORT HERBICIDES IN THE CHESAPEAKE BAY ST. MICHAELS, MARYLAND JULY 18, 1978 p ARTIC/p^ N % sT Environmental Protection Agency Chesapeake Bay Program % XL CITIZENS STEERING COMMITTEE DOCUMENT NUMBER 1 ------- INTRODUCTION The Citizens Steering Committee of the United States Environ- mental Protection Agency Chesapeake Bay Program is one of the most important elements of the Public Participation Program. Citizen Steering Committee members represent many interests and geographi- cal areas. The Committee serves as a focal point for Bay-wide citizens' concerns regarding water quality planning and management issues affecting the Bay. In order to provide citizens with timely information on a sub- ject of interest and importance, the Citizens Steering Committee sponsored a Forum on Herbicides in the Chesapeake Bay, the proceeds of which follow. Under the leadership of Dr. L. Eugene Cronin, Chesapeake Research Consortium, a highly diverse group of capable persons, bringing a strong background in the subject material, were assembled. Rather than confining the agenda to formal presenta- tions, a series of pertinent questions were posed to members of the ¦forum panel. Out of this format, a useful and informative body of knowledge was presented. The Citizens Steering Committee wishes to thank all panel parti- cipants and members of the public for their thoughtful contribution to the Forum on Herbicides in the Chesapeake Bay. ------- For information concerning the EPA Chesapeake Bay Program write to the Citizens Program for the Chesapeake Bay, Inc. Public Participation Program at: 5 East Queen Street 48 Maryland Avenue Hampton, Virginia 23669 or Annapolis, Maryland 21401 ------- TABLE OF CONTENTS Page Foreward i Agenda ii Overview iv Introductory Comments: Dr. L. Eugene Cronin 1 Dr. Joseph H. McLain 2 Questions Posed by Moderator and Discussion 7 Questions from the Public and Answers 49 ------- Citizens Program for the Chesapeake Bay, Inc. Public Participation Program Citizens Steering Committee 5 East Queen Street Hampton, Virginia 23669 1804)723-0774 Mr. Cranston Morgan, Chairman Mrs. Elizabeth Bauersis Mr. Allan G. Clark, Jr. Mrs. Anita H. Conquest Honorable C. Bernard Fowler Mr. John Gottschalk Honorable Gilbert Glide Mr. Walter Harris Mr. Phillippe Masiee Mr. Donald W. Mathias Mrs. Barbara Racine Mrs. Merilyn Reeves Mr. Russell C. Scott Mr. Larry Simns Mr. Lawrence T. Whitlock Mr. Donald A. Wilber Mr. George M. Hagerman, Executive Secretary FORUM ON HERBICIDES IN THE CHESAPEAKE BAY Tuesday, July 18, 1978 Martingham Harbourtowne Inn St. Michaels, Maryland MODERATOR: Dr. L. Eugene Cronin PANEL MEMBERS: Dr. David Correll Dr. Stanford Fertlg Dr. Joseph H. McLain Dr. Thomas Munson Mr. Loy Newby Mr. Robert Orth Dr. James Parochetti Dr. Stevenson Dr. Vernon Stotts Director, Chesapeake Research Consortium Smithsonian Institution, Chesapeake Center for Environmental Studies Pesticide Assessment Staff, U.S. Department of Agriculture Chairman, Bay Grasses Oversight Committee Annapolis Field Station, U.S. Environmental Protection Administration Agricultural Division, Ciba-Geigy Company Greensboro, North Carolina Department of Invertebrate Ecology, Virginia Institute of Marine Science Department of Agronomy, University of Maryland Horn Point Environmental Laboratories, Center for Environmental & Estuarine Studies, University of Maryland Wildlife Administration, Maryland Department of Natural Resources i j ------- AGENDA Introductory Comments: Dr. L. Eugene Cronin Dr. Joseph H. McLain Questions Posed by Moderator: What quantities of which herbicides have been used since 1965 in Maryland and Virginia? Where? At what seasons? What is known about movement of the prin- cipal herbicides into tidal waters? Where and in what quantities have these herbicides been observed in Bay waters, sediments and biota? What are the effects of these herbicides on Bay plants and animals? Have herbicides affected the abundance or health of submerged aquatic vegetation in the Bay? Who is doing what research on related problems? What research is planned in the next year? What additional studies must be undertaken to achieve adequate guidance for management decisions? Questions from the Citizens Steering Committee. Questions from the Public. ------- OVERVIEW Only full review of the Forum Report can provide accurate information on the data which have been obtained, the research underway and the opinions and conclusions held by the members of the Panel. The reader is urged to read and use all of it. It is apparent, however, that a shorter overview of highlights can be of service to readers who wish to know the nature of the discussions and the degree of our present knowledge of any possi- ble relationship between herbicides and the aquatic vegetation of the Bay. The following statements are provided for that purpose. They are the impressions received by the chairman -- not formal agreements by members of the Panel. * The Panel included almost all of the scientists who have recently conducted research on this set of questions in the Chesapeake. * Aquatic vegetation has many values in the Bay and its tri- butaries . * The possibility of relationships between herbicides from no-till farming and aquatic plants has created exceptional interest. * Wide-spread sampling in Maryland indicates a decline from 1971 of about 50% in the number of sites (among 625) which are vegetated in Bay waters. * Considerable and increasing quantities of no-till herbicides (principally triazines, linuron, alachlor and paraquat) have been used, mostly during spring months, in Maryland and other states in the Chesapeake watershed in recent years. ------- * Sampling and analysis for herbicides is difficult in water, on suspended sediment, in bottom sediments and in animals and plants. * Observations indicate that a small percentage, on the order of 15 to 2%, of applied herbicides may be carried with water and sediment running off the land. * Limited sampling found small quantities of herbicides in river water year-round, varying with rainfall. * No-till agriculture usually reduces herbicide and sediment run-off below that from conventional tillage. * Herbicides have been found in Bay waters at low levels of concentration, generally decreasing down the Bay. * Herbicides have been reported from some of the sediment samples which have been analyzed, but the pattern of dis- tribution is not yet known. * Suspended sediments may be important in transporting organic chemicals since they carry high concentrations of such materials. * In limited laboratory experiments, herbicides significantly affected Bay plants, but the level of concentration which is damaging is not yet established. * The observed distribution of herbicides in the Bay does not coincide with the presence or absence of plants. * Several possible causes may be contributing to reduction in plant populations, including turbidity, herbicides, chlorinated hydrocarbons and climatic conditions. * There have been previous die-offs in the Bay grasses, certainly for eel grass in the lower Bay area. ------- * Several major programs of research are underway or planned that will provide new information on submerged aquatic vegetation. Some of these will yield new or better data on herbicides and its potential or real effects. Most, but not all, are funded under the EPA Chesapeake Bay Program. * Response to questions from the audience: The Panel varied in their opinion on whether or not herbicides have affected vegetation. Some felt that they have not, some cannot now conclude, and all felt that additional research is essential. The process for testing and approving hazardous materials has failed in some past cases but is now more rigorous and extensive than ever before. Good farming practices are of high value in reducing run-offs of sediment and chemicals. There is much, much more in this Report. Only reading of the complete record of the Forum can provide the full image of frank and thorough discussion provided by the Panel. The members of the Panel hope that this Report is useful to the Citizens Steering Committee and to all of those who are interested in the welfare of agriculture and of the Chesapeake Bay. L. Eugene Cronin, Chairman vi ------- FORUM ON HERBICIDES IN THE CHESAPEAKE BAY July 18, 1978 Chairman: Thank you very much for coming. It is good to see this expression of ccnsi derable interest by a w.i de variety of people about an important topic. In setting up this forum, we thought that the most effective l.hinp, would be to bring in front of you the individual people who have the best original information, the best knowledge about the topic of Herbicides in the Chesapeake Bay. We will not include the herbicides on land or in other places, except as they affect the r> ay. Our boundary is the edge of the Bay, although all of us recognize that what happens on the other side of that boundary is extremely important. Our focus is on the water in the Bay, the sediments in the bottom and the animals and plants living in that system--and in trying to understand the relationship between these things and the general group of chemical materials we call herbicides. This is an important topic to many people and to many interests as evidenced by your presence here tonight. We thought it would be a healthy thing to bring together, for the first time, the in- dividuals who have done the research, made the measurements and have the data. We have asked them to convey to you clearly and correctly what we do know and what we don't know now, what research is going on, what research is planned, what else is needed to solve the question whether or not herbicides and plants are seriously related. i ------- The format will be as follows: I will ask the panel a series of questions and ask that they make short direct comments and provide data or information on that question. After we have completed the set questions, the discussion will be open to the members of the Citizens' Steering Committee, a very important group and our primary audience tonight. They have asked that this information be brought to them so that they can provide useful advice to the Chesapeake Bay Program. I will then open the floor to the audience and welcome any brief comment or question that you may have. Again, we wish to limit the Forum to the re- liable information available and keep side issues to a minimum. Our interest here is in the Bay and what needs to be done. (Introduction of the Panel on Herbicides and of the members of the Citizens' Steering Committee present) I would like to ask Dr. McLain to make a background comment. Dr. McLain: I want to give you briefly some history of my interest in the Bay. About two and a half years ago, during a duck hunting expedition, I asked what had happened to all the grass, and my host said, "Well, it's the run-off from herbi- cides and no-till farming." When I asked how he knew, he said he had heard it from "them." I have found out in years past that "they" are not a very reliable source, and so I checked. I looked on both sides of the creek, and there were no tillable fields back for a mile or two. About a week later, I was down 2 ------- along the Honga River. If you know Dorchester County, you know that that is 90 percent swamp, that it is a place for eels, flies and muskrats. Hope no one takes exception to that, I like it down there, too. And again, I looked and there was absolutely no grass where it was at one time plentiful and verdant. I don't know how to describe it, but it was just a wonderful place and we used to always have lots of grass, good crabbing, fishing and hunting. At that time, Louis Goldstein, the Comptroller of the State, was with me and I waxed a little enthusiastic about this and told him, "Do you realize that the Chesapeake Bay is not going to be the Chesapeake Bay it is now? Where are the crabs?" The grass plays a very important part in the life cycle of the minnows, I understand. I am not a biologist, those are just some of the things I have picked up. Also, we are losing shoreline. This last eight years we have lost approximately five feet along a mile and a half of shoreline to erosion because we have no way to control it. I think the most important part of submerged aquatic vegetation is that it iis.!'a sure: inidlc'at'br of 1;he hea'lth of the Chesapeake. Because e-v&n [though ist' i-s; &hiy one part o'fJ the' whole ecological chain, i t-iisl v-ery", very i-mportaht. 'If therfe i's much turbidity, that means; that .the water ifs too cloudy, and' i'f tne sunlight does not penetrate Łars enough,' irf order to allow 'the aquatic plants to mature and revse'edf frh'erriselves; 'then you are going to 'have bad grass and you are going to have bad water because it is a vicious cycle. 3 ------- Submerged aquatics have a mucilaginous coating on their leaves and any of you who have been around the water know you can feel it and know that it is somewhat slippery. You will notice that it is often dirty. What that means is that the grass is a filter, so that the more grasses you have, the less turbidity you have and the less turbidity you have, the more grass and so the whole thing works together. On the other hand, the less grass you have the more turbid the water will become. I thought we should try to do something about this and wrote a letter to the Governor asking if we could start a program to restore the grasses and to find out the cause or causes of their disappearance. A joint resolution was introduced into the House and the Senate and was passed by the legislature, and we got started. We formed a little unofficial committee -- Gene Cronin and Vern Stotts were on it, and recently Jim Parochetti — to try to do something to bring the grass back, not thinking that we could change Mother Nature, but that certainly we could help. There were periods when grass was gone, and there is lots of grass in other times, and there is lots of history involved which says that these things are cyclical. You will have lots of grass one year and not so much the next, but no one knows the answer to it and nobody knows the frequency or amplitude of the cycles. But we could help nature in its own efforts for restoration. On this graph these red dots represent a sampling ,of 675 stations throughout the upper Bay. (Question) '"Are they.all above the Bridge?" (Answer) "They are all in Maryland -and exclude 4 ------- the Potomac." At each station, grab samples were taken and checked to see whether or not any vegetation was present. In 1971, 29% of the stations sampled had vegetation. In 1972, it was down to 21%; in 1973, down to 11%. A slight increase to 15% occurred in '74, but there was a decrease in '75 to nine percent, and another small rise to 15% in '76. Now mind you, these data are only good to plus or minus five percent so if we have eight percent, we are not sure what that really means. The real figure could be 12 or could be four percent. It is not healthy that vegetation has disappeared at half of those stations in a period of one, two, three, four or five years. This big disappearance start- ed abcut the time of Agnes, the hurricane, when we had to open the Conowingo Dam or drown the people in Port Deposit, and we thought we'd better open the dam! So, we did get an awful lot of detritus, top soil and trash from New York and Pennsylvania into our Bay. But there was nothing we could do about it, nor can we usually do anything about an act of God, which is what that was. But what we can do, hopefully, is to bring one of those low periods back a little bit sooner. So as part of this Bay Grass Committee we have undertaken some experimental plantings. In the Grays End Creek area where no-till farming is more prevalent than it was five or six years ago, we do have lots of grass. A private owner planted $65 worth of sago pond weed tubers -- rr.aybe that planting did not do it all, but it is coincidental that there is grass there now, including redhead grass and widgeon grass. 5 ------- And we had five or six thousand blackheads hanging around all last year, too, so this was important to us. We all talk about the "cause". I want to give a few cautions. There are many things that are probably responsible either singly or in combinations of two or more. We have temperature problems, salinity problems, herbicide and pesticide problems, turbidity, sedimentation, and oil spills and we do have traffic up and down these waterways of ours, which is what they are for. It is for enjoyment, but much of that traffic causes extra turbidity and a problem in the grass. Now put all those factors together and maybe only one of them is responsible for damage. Maybe it is mainly turbidity, maybe it is mainly salinity, but my bet will be that we will find that it is a combination of, in some places, herbicides and something else, or of turbidity and something else. Unfortunately, nature is complicated and we cannot just make a formula and solve it all. This is one of the reasons we have meetings like this. I want to make one other comment. I have lived long enough to see that people, well-meaning scientists, well-meaning federal agencies, well-meaning organizations, do not consider always the side effects. Sometimes the cure is worse than the disease, as witness Lake Erie. This is a pollution problem. The Food and Drug Administration once outlawed use of non-biodegradable deter- gents. Now these were petroleum sulfinates and you have all seen the horror pictures of big foam balls running and blowing down the rivers and streets, so those were outlawed. And what we did then § ------- was demand that phosphate detergents be used. The phosphates then became a beautiful nutrient for all the algae that would want to grow there in Lake Erie. So we have eutrophication of Lake Erie. Now here is what has happened -- phosphates have gone to silicates. Silicates, when they hydrolize, will give us even more turbidity. I am not too sure that these things are carefully studied, but they should be. So any cures and any other management steps that we come forth within this program have to be evaluated very, very carefully to see what the side effects will be. Nature is awfully funny. You bring in a lady bug to feed on some pest and the first thing you know, you have got too many lady bugs. But just as soon as you pick one side, you change the other side. So I pray for caution. I hope that we will get it. Chairman: I have a map here which was prepared by the Corps of Engineers from remote sensing data by NASA. It is a very useful land-use map of the Chesapeake Bay region. The different colors show agricultural land, forest land, metropolitan areas, industrial sites and wetlands. The metropolitan areas, shown in blood red, are where the people are and that is where many of our problems originate. Maryland has a higher percentage of land in agricultural use than Virginia, which shows large forests. This map can be a reference in our discussion. Chairman: What quantities of which herbicides have been used since 1965 in Maryland and Virginia, where, and in what season? Dr. Parochetti: I have prepared something on the major herbicides used in production of corn and soybeans in Maryland. 7 ------- In no way is it a complete survey of all the herbicides, but only the major ones we are concerned about. I have worked up some good estimates because good data for Maryland as an individual state is not available to the public. These are estimates based upon my talking with people and my own feelings, having worked with farmers in the State. Table 1 lists estimates for triazines (mostly atrazine, but including simazine and cyanazine). Table 1. Corn acreage and total tons of triazines used in Maryland for corn production in selected years. Corn acreage Tons of total triazines used 1965 565,000 150 1971 no tillage conventional 100,000 520,000 454 1975 no tillage conventional 328,000 327,000 613 1977 no tillage conventional 363,000 363,000 690 It was not until about '69 that no-till started out moderately but by 1975 about one-half of our corn acreage was in no-till cul- ture, primarily on the Western Shore. I estimated-that two and one-half pounds of total triazines were used in about 99 per- cent of the no-till corn acreage. That may be a very liberal estimation. The rate of triazine used has increased dramatically from 1965 to 1977. It pretty well stabilized on the amount of actual material applied per acre, but the acreage of corn in 1977 is higher than in 1975 so the total amount increased. This is S ------- only for Maryland and this is for all of Maryland. Some of the data that you worked up, Court, was only for the Eastern Shore. I estimate that about one and one-half pounds of triazines per acre were used in conventional corn culture, lower because in conventional tillage there are a number of non-triazine herbi- cides used in combination with triazines. Table 2 summarizes the use of linuron in the State of Maryland. Table 2. Soybean acreage, percentage of soybeans treated with linuron, and total tons of linuron used in Maryland for soybean production in selected years. % of soybeans treated with Tons of Soybean acreage linuronl/ linuron used 1965 conventional 207,000 50% 25 1971 no tillage 1,000 65% 36 conventional 224,000 1975 no tillage 74,000 conventional 226,000 1977 no tillage 108,000 conventional 212,000 70% 52 75% 60 1 / — Rate is about 0.5 lb/acre (active ingredient) There is a more diverse use of herbicides in soybeans because the individual herbicides available for soybean production do not control as broad a spectrum of weeds as some of the herbicides used for corn. Most of these herbicides are applied from the end of April until about the end of May for corn and then from about the middle 9 ------- of May to about the middle of July for soybeans. For small grains, herbicides are applied in the fall or late winter, but these are very short residual herbicides such as 2, 4D or dicamba, used on a small percentage of the acreage. Simazine and several non- triazines are used on alfalfa in the fall or late winter on a small percentage of the acreage. Based on the data I have, I would not disagree at all. I am sure we are in the ball park here. I mean if someone wanted to do some other calculations you might get another one-half pound more per acre, you might get a few tons more, but in magnitude, and I know that with your data, Court, we looked at earlier this week, and you are in the same magnitude as we are. It is difficult to come by accurate figures because the com- panies don't publicize these, that is they keep rather secret and if they do publish any figures, they do so by regions and not particularly by states. Question: Do you have any data on other herbicides? Dr. Parochetti: We have some estimations: Alachlor is used both in corn and soybeans. With just a top-of-my-head guess, about 25 to 30 percent of the acreage in corn and soybeans gets some alachlor. Paraquat is used for almost all the no-tillage pro- duction. We have about 50 percent of our acreage in no-tillage corn and about 30 percent in no-tillage soybean production. There is another substitute but it is more expensive--it is called Roundup . Dr. Correll: I don't want to talk about application rates be- cause they are not my bag, but I do want to point out that the question is a little bit narrow in scope. We are talking about the Chesapeake Bay, not Maryland and Virginia. A lot of the appli- 10 ------- cation of herbicides is in other states, Pennsylvania, New York or West Virginia. I did a quick calculation, partly using Jim's figures and also using available data on land-use and watershed use. For the whole of the Chesapeake Bay, I calculated that approx- imately 15,000 tons of herbicides are used per year for all types combined. This is a rough figure -- it could be one-half that or double that. If you are talking about the Chesapeake Bay area a- bove the Potomac River, 90 percent of the drainage is not in Mary- land, but in Pennsylvania and New York. So it is a relevant point. Dr. Newby: Relative to the total drainage of the basin of the Bay, we have calculated, fairly accurately, that the total amount of triazines applied probably is below 1500 tons. Chairman: What do we know about the movement of the principle herbicides that have been cited into the tidal waters of the Chesapeake Bay system? Dr. Correll: I think we are the main group that has been measuring the movement of herbicides into tidal waters in the area and we have been doing that now for the last three years. I can tell you what we have found in the Rhode River, which is a very small part of the Chesapeake Bay. During the growing seasons of '76 and '77, we looked at the efficiency of movement of the principal herbicides used in the Rhode 'River area, specifically' atrazine and alachlor, into tidal waters. We have surveyed the usage and actually measured the application rates on sub-basins^ and have measured the delivery to tidal waters at the bottom of- the basins.' Both years were some- what, drought years, they .were dry or very1 dry, so that these data only apply to those conditions.. They'might be different in wet 11 ------- years such as this year, but we have found that one to two percent of the atrazine applied was actually delivered to the Chesapeake Bay and about .1 to .3 percent of the alachlor went1 into the Bay. We can speculate, and it would be logical to think, that in a year such as this with more rainfall, more is being delivered. We were concerned about when herbicides are delivered and at what concentrations. I think the most important point to make here is that the herbicides were delivered all during the year, not just immediately after spraying. In fact, some of the heaviest deliv- eries were in the fall because rainfall was heavier then. Last summer was very dry with considerable amount of crop damage from drought, but when it began raining last fall we got considerable delivery of herbicides into the Bay. The same thing happened in 1976. These herbicides were not degraded before the fall, they were still present in significant amounts. They are being trans- ferred through the system slowly so that the time they are deliv- ered onto the plants is not the same as the time they are deliv- ered onto the fields or into fresh or tidal waters. We see that in our data because we have various sampling stations in different parts of the watershed. The peak deliveries are during storm events, severe storms and hard rains. The bulk of the delivery is in solution rather than with particulate matter during those storms. Another thing I might mention is that you should not make an assumption that all the delivery is in run-off. We have also been measuring delivery in terms of dryfall which is dust settling out of the air and from the atmosphere in rainfall,which is washing things out of the air. Our conclusions are that perhaps 12 ------- one-third as much is delivered that way as in run-off. Thus, there are two ways by which atrazine and alachlor are delivered. Other herbicides may be different -- some evaporate more easily than others but these two herbicides are the major ones used in our area. Alachlor is used more than atrazine, but it is not delivered to tidal waters as efficiently. It is bro- ken down more rapidly. These herbicides work synergistically in corn fields to kill weeds, so we are concerned about possible interactions in the Bay as well. Chairman: Are there other comments about the movement into tidal waters? Dr. Stevenson: As far as other herbicides, we did find some data on 2,4D which indicate that it is about two percent possible leakage. Linuron is about .3 percent and trifluoralin is about .05 percent. There are other studies done in other areas of the country (included in our recent literature review on SAV's) but we took a figure that would probably be more applicable to the Bay region. The atrazine figure of one to two percent that Dr. Correll gave is among the highest thus far reported for the herbicides that we have worked with so far. There are a couple of other studies but we do not feel that their data was applicable to the Bay. Dr. Newby: I would not disagree with either of the comments that were made. Our measurements, not isolated to the Bay, indi- cate up to one percent total run-off' of atrazine. Dr. Parochetti: I am not going to disagree, but question. It is hard to believe that you are finding atrazine coming out 13 ------- of the experimental areas in the fall. As a scientist, I feel that I can question that, because I have done some research my- self over the past five years on the dissipation of atrazine and simazine in no-tillage and conventional corn and bio-assayed for herbicide residue with barley in the fall. I used rates of two pounds to sixteen pounds per acre of atrazine and simazine. I would disc the land in the fall, plant barley, and harvest it the next spring to see how much residue there was from atrazine and simazine. Only in 1976, which was a dry year, did herbicide residues result from application rates as low as four pounds per acre. In other years, I applied up to eight pounds of simazine (twice the recommended legal rate) with no detectable residue. I wanted to say something about work done by Buchanan and Hildebrandt in Auburn on the dissipation of atra- zine and how pH affects atrazine persistence in the soil. If you have neutral soil, the triazines are really going to stay around for a long time. The half life of atrazine when it is in acid soil is about 30 days. Biological activity from my experience is about six weeks but that does not mean that there is not some atrazine there. People who have reported on it say that there is detectable atrazine ten months after application. Dr. Correll: We are not talking about in the soils. We are measuring atrazine in the soils, too, and it is detectable the next year, but we are not talking about very much- detectability the nex:t year. I would agree with, yon that it can disappear very rapidly in the surface of the sail.. This can. be due to either leaching; down into the soil or being; eroded, but mostly Leaching L4 ------- down and being degraded. We are doing quite extensive studies on that in the same area. But what I am talking about is delivery into the Bay. The material that is being washed off the soil be- fore that happens is being stored somewhere along the way and it is delivered year round. For some confirming data, I think I could turn to Tom here who has been looking at that kind of thing in a different system. Dr. Munson: We have been monitoring atrazine and simazine in the Susquehanna River at Harrisburg. We chose Harrisburg, even though it is somewhat distant from the Bay, because the U.S. Geological Survey would provide us with very fine samples of the River at that point. They provided us with depth-integrated sam- ples at a point where they are measuring the river flow. We wanted to establish a budget of atrazine and simazine going past that point for a year. We would have preferred to be at Conowingo Dam, but we would not get the logistics squared away to get the sampling done. In regard to delivery of atrazine and simazine, our results are similar to Dave Correll's. We find that the a- mount is correlated with rainfall, not with application. I have data here from June to December 1977, which show that, while the peak concentrations of atrazine and simazine occurred in the June- July period, four times as much was being transported by the River in November when there were higher river flows. The curves are almost superimposable for atrazine and simazine. Dr. Parochetti: I find it hard to believe, but it is a matter of interpretation. You have looked at the data and I have not seen it. I know that when I am working on agricultural land, I 15 ------- don't get biological activity from the site that you apply it on after a certain time. Dr. Munson: I don't feel that it is a matter of interpretation. The data seem quite straightforward. Chairman: Is there additional comment or data? Dr. Parochetti: Yes, I was talking about persistence in soil. Dr. Newby: We have monitored many rivers around the country and again, I guess I am agreeing in a way, but the peaks that appear occur in the spring after application, after the first heavy rainfall. Subsequent peaks occur with subsequent rainfall events. We have not in any of our monitoring seen a significant peak in the fall. This is really what David has found and, I suppose, Tom. But the audience must realize that the amounts that we all measure in these streams in the fall are really small. We are talking about less than one part per billion. We are talking about a huge watershed. If you consider the amount from the total watershed -- less than one part per billion -- and if you calculate the total poundage (Tom, you had about 2.7 metric tons entering the Chesapeake Bay during a half year period), we find that we are talking'about a minute amount. Jim, from that aspect, we are seeing those small amounts. Dr. Parochetti: I thought it significant you know about the half life of the triazines and the fact that they are detectable in very small quantities at the end of the season, but they are not affecting rotational crops to any appreciable extent. Simazine is more persistent. In a study done in Kentucky under the no- tillage method, less than 15% was biologically active there after 16 ------- six weeks. In conventional tillage, it was more than 50%. It is not dissipating as rapidly under conventional tillage methods. I thought this was an important point. A lot of people have been pointing the finger at no-tillage as a cause of having more herbi- cide running off. There is clear evidence that the herbicides, particularly simazine, dissipated in Kentucky much faster in no- tillage conditions. For linuron, under normal conditions biologic activity in the field does not exceed six weeks. There is always a possibility that analysis could detect linuron toward the end of the season. It is not as biologically active nor as persistent as atrazine or simazine. Tables 3 and 4 summarize herbicide losses by runoff as reported in the scientific literature. Chairman: Is there any other information available on move- ment of herbicides into tidal waters? Dr. Correll: I want to make it clear that our Rhode River studies are on conventional tillage and I would agree with Jim that it stands to reason that no-tillage should have less herbi- cide contamination in run-off than conventional tillage. Dr. Munson: I did not go into all the work we have done at the Annapolis Field Office of EPA. We made several sampling runs down the center axis of the Bay from the Susquehanna Flats down below the Bay Bridge and found a pattern consistent with the idea that the major input of the atrazine and simazine to the upper Bay is carried by the flow of the Susquehanna River because we find the highest levels in the upper portion of the Bay and then a drop in amount like a dilution effect. As Loy Newby points out, 1 7 ------- the levels found are low -- one part per billion level being the highest, and these levels are similar to the levels we measured in the Susquehanna. We also collected a series of samples in the Potomac River, and, once again, found trace levels of atrazine and simazine. In the Susquehanna River, there is considerably- more atrazine than simazine -- about four to one or three to one. In the Potomac, however, the ration is different. Relative to atrazine, simazine is much higher than in the Susquehanna. Analy- tically, all of the atrazine and simazine concentrations found were low -- at the level of parts per billion. Whether or not these levels have biological effects remains to be seen. The amount of atrazine passing our sampling point in Harrisburg in the half year June to December was something just less than three metric tons and half a metric ton of simazine came down. Chairman: I would like to interject a comment or two from the chair. It is important to recognize that the chemical materi- als we are talking about are complex organics which are difficult to quantify. They are measured by very indirect means. On the other hand, our chemical analytic techniques have become fantastic. We are no able to measure things in extremely low quantities. There has been a real revolution in analytic capability. That does not mean that it is easy, that results are always consistent or that the numbers are always precise. They are difficult to work with. If I may try to summarize what has been said here, there are indications from a very limited number of data that there is input of these materials into the Bay. We don't know enough a- about the seasonal or other characteristics. The concentration 18 ------- Table 3. 11T h i c i < 1 c So f 1 tYPe S lope Rate of App11ca t ion Herbicide Loss Reference — kg/ha — —% of tota1 applled— S 1 irtnz i ne Rriyne silt loam 12-18 1.70 2.2k 2.10 0.28 Trfplett, 1978. Rayne silt loam \h 2.2k 1.79 3.80 0. \k Rayne silt loam 12 k.k8 1.7 Keene silt loam 13 2.2b 5.k Coshocton silt loam 10 1.12 0.06 Musk!ngum silt loam 17 1.12 0.0k L i nuron Mhoon s i1ty clay 1oam 0.2 2.2k 2.2k 2.2k 0.0k 0.02 0.29 Willis et a 1., 1975. ------- Table 4. Summary of Atrazine Runoff Losses S lope Rate of Applicat ion Herb ic i de Loss Reference Cl-cII sondy loam I do silt loom Roync silt loam _ _7 _ _ fo H.mjci's town silty clay loam 14 6.5 10-15 Ungerstown sllty clay loam 14 lkic|';rstown sllty clay loam 14 12-18 1-10 kg/ha -- -70 of total applied- 0.6 1 . 1 2.2 4.5 6.7 9.0 3.4 3.4 2.2 0.5-5 2.2 *».5 1.7 0.8 1.73 3.67 2.50 2.17 2.32 2.98 2.0 18.0 16.0 2.6 5.0 4.8 < 1.7 Ha I 1 et aj.,, 1972 1.2 White et §1., 1967 R i t ter <^t a_L , 1974 Ha 1 I and Pawl us, 1973 Hal 1 , 1974 Tr iplett et aJL , 1978 CorrelI, 1977 ------- is very low, but the material is present. However, the observa- tions that we have heard are from only two places, one small watershed on the Western Shore and the Susquehanna River, a fundamentally important place because of the contribution of one- half the water of the Chesapeake Bay system. But I do want to in- dicate the limitations on the useful data we have on this particular part of the question. I would also like to say that every farmer I ever knew wants to use his materials on his own land and he is most interested in not having it cross his fence line. He will do what he can constructively to get complete and efficient use of the material. There are agricultural techniques which favor that, and I think that some of them have important advantages. Chairman: Where and in what quantities have these herbicides been observed in Bay waters, sediments and biota? Dr. Ne-wby: These three slides will depict data on atrazine residue in water and the bottom sediments in the Bay. Samples were collected last year (1977) by Dr. Munson, Dr. Orth, Dr. Wolfe of the University of Maryland and by our own people. June 1977 -- these are the values we measured and, as you can see, the values decrease as you move down the Bay. This is ex- pected since the Susquehanna is the primary discharge source. Let me point out that these values are in parts per billion and in most instances are less than one part per billion. The "S" indi- cates a sediment sample. At Cove Point, a sediment sample contain- ed no detectable residues at our sensitivity level of 20 parts per billion. July 1977 -- we apparently have had the field applications, 21 ------- and rainfall events have occurred upstream with subsequent wash- off of residues into streams, then down the river into the Bay. Again, notice the descending order of values. The highest value -- 1.05 parts per billion -- is in the mouth of the Sus- quehanna. This is in the lower Bay. Samples were provided by Dr. Orth who collected them in September and October; again the "S" denotes bottom sediment. This time our sensitivity level was four parts per billion. We did not see any atrazine in the sediment. The values in the water are similar to those observed upstream. Gen- erally, the average atrazine residue value in the Bay was 0.5 parts per billion. We have analyzed several sediment samples from the Bay proper and from several of the feeder streams in conjunction with Mr. Stotts this year in the Honga, Chester, and Choptank Rivers. Per- haps he can explain the program later. We have analyzed sediment and water samples through May and we have not detected any residue in the sediment. The values in the water again follow a descending order; at the top of the Bay, the highest values are obtained at the headwaters and at the mouth you find the lowest values. For the Chester and the Choptank the values are again less than 0.5 parts per billion. In the Honga, we have not detected any resi- due yet. You might have something to say about these data later, Vern, in relation to the weed population. We have analyzed one group of samples — if I can quote your data, Mr. Cronin, that had detectable values in-sediment. Mr. William Cronin: I collected water and sediment samples 22 ------- m the Bay proper, above the Bay Bridge in the settling-out area for the Susquehanna. These are the only sediment samples we have analyzed that have detectable atrazine residues. The maximum level detected was 25 parts per billion; an extremely low value. As far as I know, no one has analyzed any animals or plants. We hope to do that this year. We have no reason to suspect that atrazine residues will be present in plants, shell fish or in any other organism in the Bay -- but we will analyze available samples. Dr. Correll: I am afraid it is not that simple. I would like to begin by saying that I would agree with the numbers and in general with what Loy has presented. They do not really differ from ours. But, I would like to point out that there are a lot of other kinds of samples to look at in the Chesapeake Bay and we have been looking at different kinds of materials to which plants are exposed. Joe said to begin with, plants settle out sediments. The leaves are always covered with sediment. The sediments which settle out on the leaves are the fines that don't settle out other- wise. They have a lot of surface area and a very active surface for binding pesticides. So we have been looking at suspended sediment, the stuff that makes the water turbid out in the Bay. In 1976, a storm event occurred which resulted in a lot of turbidity in the Rhode River, and every place else we were study- ing on the Eastern Shore as well. Afterwards, and this is just a rough correlation, all of the plants at all the stations we were studying died. These included about twelve stations on the Eastern Shore and five stations in the Rhode River. Durinp ------- that storm event, we sampled in the Rhode River and the con- centration of atrazine was one-half part per billion in the water. That was not much different than what Loy was talking about. Now the concentration of atrazine in the suspended sedi- ments was 560,000 parts per billion or 560 parts per million, on a weight basis. On a volume basis, it is nothing like that as- tronomical, but the plant is seeing what settles out on its leaves, by weight, not the volume it came from. We call this a parti- tioning between the concentration in the water and the weight of pesticide per weight of sediment in the suspended sediment frac- tion. Those values were high, not average. That was after a storm event. We have looked at concentrations in the surface slicks in the water which the leaves are in at low tide. There is a thin oily slick on the water and this is not oil from tankers, but from natural causes. If you look around tidal marshes at low tide you will see slicks. There is a partitioning there as well be- cause the herbicides are more soluble in that organic slick. The concentration there was four parts per billion. That is not much, but it is quite a bit higher than in the water. Also, we looked at the bottom sediments and there is some question about the accuracy of that data.. It can be. challenged and people have challenged, it already, claiming: that we don't have a'de-- quate technology for looking atr the bottom sediments. But with the methods we used, it came to 0.8 of a. part per million, that is 800 parts per billion, the highest we have seen ia bottom sediments. 24 ------- This is in the surface of the bottom sediment, not a big scoop of bottom sediment. It is taken in the surface layer because that is where the roots of the plants are, and, of course, that is what has settled out recently. We also have seen herbicides at these stations. I would like to point out also that we have not just found them in the headwaters where the water comes in from the run off. We have found them in the open Bay as well. We have sampled around the Poplar Islands which the Smithsonian administers and we have found concentrations almost as high as Rhode River in the summer of 1976 a little bit later in the season. The plant is exposed to different fractions in the water, the suspended sediments and bottom sediments, and we really don't know enough about the physiology of these plants to know how it relates to those sources. We are concerned about the micro-environment situation. I am not saying that these things have killed the plants, I am saying that you had better be a little more careful, look at more factors, look for the interactions, look for synergistic affects with not just other herbicides, but other environmental factors as well. These include stress on the plants that they undergo naturally at the same time and shading factors which are going to cause effects similar to herbicid.es. It is a very complex picture. Chairman: Are there other data? Dr. Munson: I- like Dave ' s "approach to looking at concentra- tions on the suspended particulates -- something that has inter- ested me for quite a while. We made a step toward looking at that 25 ------- by filtering the water and then analyzing the suspended particu- late that we filtered out and analyzing the water which we had filtered. Unfortunately, the is not an easy experiment to do be- cause of the very small amounts involved. Dave's group employed some very special techniques to be able to obtain their data. Our tentative figures suggest that at least 80% of the atrazine in the whole water (that is water plus suspended sediment) came through the filter and therefore was apparently dissolved in the water. Unfortunately, the analytical method did not have enough sensitivity to measure what was on the filter. Assuming that 20% of the atrazine in the whole water was on that fine material that stuck on the filter, one can calculate fairly substantial concur. - tration factors -- on the order of at least 5,000 times the con- centration in the water. This is an experiment that I think merits careful attention in the future. Question: Would you expect to find these in the biota, either in plants or animals? Dr. Newby: I can only talk about what research has been done in fresh water systems. We know that atrazine will bio-accumulate v/iih .ii. LLgurus depending on the system you are in, probably to 10 to 15 times in an aquatic species. If you consider the value in the water in the Bay, it might be there, but I doubt if your Ic.'ijtnlulogy for the organisms art experimenting on adequate to detect it. Dr. Correll: There is a sampling problem involved as well. If you go out into the Bay and pull out some Bay greases, a lot of them are pretty small filamentous plants that do not have 26 ------- great big thick leaves. They are covered with a layer which contains sediment, algae, etc. We know that this material has lots of herbicide in it and the difficult problem when you are going out to analyze a plant of this sort is to get the plant -- rather than the stuff that is adhering to it. Many people have asked us, when we are getting the kind of abrupt die-off which we have observed a number of times, why we don't run out and grab the dying plants and analyze them. First of all, they are hard to get clean without just rubbing everything off of them and I mean clean, because these sediments on them have herbicides on the sediment. Another problem is that when they die they rot away very quickly and I don't think that rotting vegetation is a very reliable thing to analyze. I think people get the wrong idea. They make an analogy in their minds with bio-accumulation of the other pesticides, especially insecticides, up the food chain and it is a poor analogy. The plants are the base of the food chain here, they are not living off the other organisms and concentrating things that way. The only way they could be concentrating some- thing is by direct uptake and they have enzymes for breaking down these herbicides after they have taken them un. So it is rep.lly not as straightforward an issue as if you were talking about an insecticide moving up the food chain. Chairman: What do we know about the effects of these herbi- cides on Bay plants and animals? Dr. Newby: We don't believe that atrazine or other pesticides are having any effects on Bay grasses. From a chronic standpoint, you know, year after year, I can't tell you they do not. But, 27 ------- based on the data we have and what we know, we would say that they are not affecting the plants; and I would even be more sure that they are not affecting the animals. We did address in some of these other questions what we propose to do to find out more and to fur- ther elucidate whether the herbicides are having an effect. But, at this point, I do not think we can say that they are or are not. Chairman: I would like to solicit from the panel any comment they have on reliable information on the effects of these parti- cular materials directly on organisms in the Bay and then we will come back to this question of have they had a general effect. Dr. Correll: I am no more willing than Loy to make a decision about the matter. I would like to explain what we have done so far. During the growing season last year, we carried out labora- tory bioassays on four different species of Bay grasses. These are called microcosms, but they are nothing more than a fish tank with fancy appurtenances. You can control the temperatures, the time of lighting and things of that sort in well controlled media and have carefully selected sediments in them. Then you put plants in and dose them with herbicides in various way. We looked at four species of grass: wild celery from low salinity water, eel grass from high salinity water and sage pondweed and horned pond- weed from intermediate salinities. We did the same experiments with all of them. First, we mixed herbicide uniformly in the bottom sediments, at given concentrations, in'16 tanks for each experiment. Differ- ent concentrations and controls were used. Then we put synthetic brackish water of the right salinity in the tanks and planted the 28 ------- Table 5. Relative Toxicity of Herbicides to Estuarine Organisms Oys tersj/ Herbicide 96-hr ECejq Shr imp2/ ^8-hr EC50 Fish!/ ^8-hr LC 50 Phytopl anktonV % decrease at 1.0 ug/ml At raz i ne D i uron Pa raqua t no effect at 1.0 1.8 no effect at 1.0 30% at 1 .0 ug/ml no effect at 1 .0 6.7 no effect at 1.0 no effect at no effect at 1.0 1.0 87 53 W Cone, causing 50% decrease in oyster shell growth. 2/ Cone, causing mortality or paralysis to 50% of adult shrimp. V Cone, causing 50'/' mortality to juvenile fish. U_/ .1 decrease in productivity (carbon fixation) during a U hr exposure to 1.0 ug/ml of the herbicide. Source: Butler, P. A. 1365. SWCC 18:576-580. 29 ------- plants. We measured their photosynthetic rates (how much they could grow in the light) and their respiration rates (how much they used up of their reserve materials at night). The problem with interpreting the data is that people are not very good at set- ting up these microcosms to really be similar to the Chesapeake Bay. We did our best and we were not that sure of the results because we did not really produce effectively what we wanted in those tanks. We obtained some data but the herbicide concen- tration distribution in the different phases in the tanks was not what we really wanted. So all we can say at this point is that, with all the limitations of what went on in those tanks, there was very severe inhibition of the growth of the plants at about one to two parts per million of atrazine in the bottom sediment. There was very mild inhibition in concentrations of a couple tenths of a part per million in the bottom sediment. However, the concen- tration in the water phase of the test was higher than we wished and we might have been affecting the plants in that way. At the end of these experiments we decided we had to go back to the drawing board and design the tank controls better than ve had the first time. We are in the process of doing that now -- we are in the middle of another round of experiments with different conditions. So we really cannot say whether or not the herbicides in the Bay are killing the plants, but we can say that concentrations in bottom sediments in our tanks such as we have in a few cases observed in the Bay after storm events are enough to affect the plants in those tanks. We cannot say that it would have happened in the Bay, though. I conclude that we need to do quite a bit 30 ------- more work along that line. Dr. Parochetti: Table 5 summarizes some data on toxicity of herbicides on estuarine organisms. Dr. Correll: Were the animals dosed with solutions of the compound or fed with foods that had that in them? Dr. Parochetti: I have not reviewed the paper. I am looking at Dr. Wolfe's data and I will speculate that it was dosed with the solution. Oysters were dosed for 96 hours and the shrimp for 48 hours, so this would be acute toxicity rather than chronic. Dr. Correll: That reminds me of a point I forgot to make. When we did our bioassay experiment, we did not get a rapid res- ponse. It takes several weeks before you see the response in the plants to a dosing or a reaction in the Bay after storm events. We don't see response immediately, we see it weeks later. But whatever causes it, we see a correlation between storms and die-offs, but it is a matter of weeks, not a day or two. Dr. Parochetti: Atrazine is a photosynthetic inhibitor -- its job is to inhibit photosynthesis in plants and this -is the major factor in killing plants in the field. It presumably would function the same in the Bay in the SAV1s. About 60 parts per billion of atrazine is the minimum concentration that affected marine algae in studies by Dr. Walsh at Gulf Breeze, Florida. It is my understanding that there are many algal blooms in the Bay. If atrazine is present in sufficient concentrations to affect plants, then it should reduce the number of blooms. Dr. Correll: We have many, many species of algae in the Bay. Many groups are more distantly related than we are to a pig. The 31 ------- data that Dr. Walsh generated in Florida was only on a couple of species. And there is a big difference in sensitivity in algae. We may be having algal problems in the Bay because of herbicides for all I know, but another point is that algae are exposed to the low concentration in the water and not as much exposed to the higher concentrations in the sediment. We are finding much higher concentrations in the suspended sediment. Chairman: Have herbicides affected the abundance or health of submerged aquatic vegetation in the Bay? Or can we tell? Dr. Newby: I think this is pretty easy to address: I don't know. I think this is what I tried to point out previously. We really can't state that herbicides have affected SAV1s and we cannot state fundamentally that they have not. Dr. McLain: If you are basing it on data, I don't want to comment. Dr. Stevenson: Based on our extensive review, we found that we did not want to make any conclusions as to what the factor was, but certainly there were some important ones and they have been dis- cussed tonight. We talked about nutrient additions to the Bay, nitrate and phosphorus loadings that may cause algal blooms and increase the problems that SAV's have in getting the proper light to the leaves. The other thing that was discussed earlier is that turbidity itself might give problems in certain areas. The other possibility is that of various combinations of herbicides. I myself feel that it probably is one of the combinations of those 32 ------- three factors that have given us quite a bit of problem in the Bay in the last ten years. There are other hypotheses that have been brought forth by other groups. One of them is that chlorine levels in the Bay are causing a lot more chlorinated hydrocarbons than we had ten years ago and that this may be a factor. There is a research group within the U.S. Department of the Interior study- ing this and they may have some interesting conclusions for us in the future. But we would not have proposed a couple of million dollars worth of research if we knew the reason for the decline of submerged aquatics in the Bay. Dr. Orth: There is one thing that is really interesting to me about the whole grass problem in the Bay. If you look at what has happened in the past to see what the grass distribution was 30 or AO years ago, you will see that the same thing that happened then is happening today. This is one of the things that has really intri- gued me a lot and one of the things that \e are really trying to look at with EPA grants in Virginia and in Maryland. This is for all Bay grasses. The dominant grass in Virginia is eel grass. This species really tolerates salinity. A lot of the fresh water grasses have been talked about today. In the 1930's there was an extensive die-off of eel grass in the Chesapeake Bay along the entire East Coast of Europe. At that time no one knew why it happened. There was also a serious decline of waterfowl and in the Virginia area a significant decline in Bay scallops. By looking at some 33 ------- of the data, to show the significance of eel grass for Bay- scallops, we will see that in 1931 for the Counties of Accomack and Northampton, there may have been a million pounds of scallops harvested from the two counties. In 1932 there was 500,COO pounds. The next year there were none and there have been no more Bay scallops harvested from these two counties since then. If you look at the record you will see that eel grass started declining around 1930, through 1931 and 1932. By 1933 there was no eel grass in the two counties. Bay scallops utilize bay grass for larvae. Scallop larvae attach to eel grass and use it to settle down and live for about two years. There is a significant relationship of die-off of eel grass and die-off of Bay scallops. The point I am really trying to look at is that in the 1930's there was a significant decline and by looking at some aerial photographs that we have from 1937, a lot of the distribution in 1977 looks identical to the distribution of eel grass in 1937. We are trying to look at enough different areas to determine if this is a picture of what is happening in the Bay. There are records, and they are not complete, that show that eel grass declined in the 1890's and the 1850's. These are serious declines. Superimposed on these are also declines of various natures and this is something that is inherent in grass beds. They are very dynamic systems but will come and go. Watermen will say the grass is here one year and gone the next. Perhaps what we have seen in the Bay in the past few years is something that is more natural. Maybe in some areas 34 ------- v.'r have gotten grass beds that are adjacent to fields or to point sources of pollution and these areas are affected, but if you will look at the past five or six years and see what has happened in the last six months, I find it very difficult to think that there has teen a man-induced change that has affected the grass beds from Cape Charles all the way to the upper Bay. Maybe there is some- thing that is intrinsic that we cannot control. It may be a natural cycle, perhaps every 30 or 40 years, with nature saying, "Grass, you're going to die this year or about this year." So, one of the things we might look at is what happened in the 301s along tie East Coast of the United States and West Coast of Europe, the de- cline of eel grass then and what has happened in the 701s. Now look back in the 30's along the East Coast of the U.S. and the West Coast of Europe, the decline of eel grass was attributed to Labyrinthula, a protozoan parasite. The popular- theory today is that the decline may have been more climatic and that temperature is a cue to die-off of these plants. The 701s have been characterized by fluctuations. The first part of the 701s was characterized by warm winters and hot summers. What I am suggesting is that maybe we are all hot on this idea of herbicides and maybe there is something more intrinsic in our system that we have not fully acknowledged. Chairman: I'd like to telescope the next two questions because they belong together. Who is doing what research related to herbi- cides in the bay? And what research is planned in the next 35 ------- year? These have recently partially merged because of the EPA Program. The Chesapeake Bay Program has awarded grants, or is in the final process of award, in its Submerged Aquatic Vegetation program and in its Toxic Materials program. Both of these have some aspects of this work in them. I would like to ask the panel to answer these two questions. Dr. Parochetti: At the University of Maryland at College Park one project by the Departments of Agronomy, Agricultural Engineering, Animal Science and Dairy Science has been initiated at the Forage Research Farm in Clarksville. They are measuring run-off of in- dicator bacteria, pesticides including herbicides, and nutrients. They are doing it in five environments; forest, conventional tillage corn, no-tillage corn, alfalfa and two pasture sites. This is the first year. Further work has been proposed to the Sea Grant Program to study atrazine degredation in estuarine systems, which is poorly understood. What is planned for the future? Hopefully, with the Depart- ments of Botany and Agronomy and the USDA will submit a project to EPA to study herbicide metabolism by phytoplankton, submerged aquatic vegetation and estuary fungi. Mr. Stotts: The Wildlife Administration is interested in Bay grasses primarily from the standpoint of waterfowl, their dis- tribution and the effects they might have on waterfowl. We have been looking at Bay grasses since the 1950's. We surveyed Bay grasses as a part of the benthic distribution studies back in the early 601s and we have been looking at the Susquehanna Flats since about 1957. We are involved in the continuation of a survey 36 ------- on the Susquehanna Flats which is done twice a year, once in July and once in October, to determine whether or not there is an increase or decrease from year to year, what animals are present and their populations, both invertebrates and waterfowl. One of the interesting things we saw in our July survey is that the Susque- hanna Flats looks worse than we have ever seen it. This includes the year after Tropical Storm Agnes. Just what is going on there is difficult to say. Just above Susquehanna Flats are rather magnificent beds of milfoil, but out on the Flats vegetation nearly disappears, at least for this July. We are also involved with the U.S. Fish and Wildlife Service in a survey of the Maryland portion of the Bay to determine from year to year whether or not there has been a change in the distribution and abundance of Bay grasses. This survey allows a detection of 5% change from year to year. The chart Dr. McLain showed did not include last year's abundance of SAV. There was a slight decrease from the previous year; some areas quite drastically. We have just begun the 1978 survey and once again it looks as if we have those oddball changes that occur from year to year. The Chester River has magnificent growth and north of there it is pretty bad. We are also involved in an experimental transplanting project in which sediments and plants are transplanted up and down three sub-estuaries; the Chester River, the Choptank River, and the Honga River. Last year we worked on the Choptank and Chester Rivers, and it was quite evident that light played a big factor in the growth and well-being of the various plants we used. This 37 ------- year we added the Honga River, because it is one area in which we felt herbicides would not be as well-distributed as perhaps the other estuaries. The interesting part we have seen so far is that the Honga River's vegetation is doing worse than in the other rivers. Dr. Newby brought some of the information that has been found sc far on herbicides in this study. We are collecting bottom sediment and water samples. They are being analyzed by Ciba- Geigy, duPont, and EPA to determine bi-weekly, or in some cases monthly, the presence of herbicides to be correlated with the vegetation into high-energy areas to see what happens. We feel that if we can get grass started in high energy areas, it will break that cycle in which the bottom remains too hard for plants to get started. In addition, USGS has a study on the Potomac River on sub- merged aquatics. The idea is to compare an intensive survey where a lot of samples are taken in small areas with our broad survey. USGS and U.S. Fish and Wildlife Service are primarily involved in that experiment. We expect to continue these this year and probably into the coming year. Dr. Stevenson: I am speaking for a group located at the Center for Environmental and Estuarine Studies, University of Maryland. EPA has funded a proposal from three of us -- Michal Kemp and me from Horn Point and Walter Boynton from the Chesapeake Biological Laboratory across the Bay. We designed a proposal around three thrusts. Orle of them is to identify which factors may be important in the decline of submerged aquatics. We are also asking the 38 ------- secondary question and that is why it might be important to have submerged aquatics at all in a Bay ecosystem. We are trying to get quantitative data on the values of grass beds in selected trib- utaries. We are using some new modeling techniques as well as tracer studies to trace the food chains very carefully. We are attempting to document when it is important tc have habitat value for perhaps rockfish or blue crabs when shedding. The other thrust that is of interest to the management people, and EPA especially, is to examine the management options we have in the Bay as far as the submerged aquatics are concerned. What does it mean to discontinue a particular herbicide or change a nutrient loading on a particular sub-estuary? What is the cost of taxpayers' money to put a sewer plant into operation versus downstream effects of not putting it in, in terms of what it means to your harvest- able and other natural resources. Since the Bay grasses are quite an important component of the Bay, you have quite a lot of work to do with modeling. Our study is hierarchial in nature, it starts in the laboratory with micro- cosms, basically fish tank size experiments, with SAV1s and sedi- ments. We then go to a situation which is more realistic--eight experimental ponds which we will be building at the Horn Point Laboratory in the next two years. From the ponds we go to field work where we will be doing extensive work with introducing blue crabs and fish to see what their survival rate is in grass beds versus adjacent areas that don't have grass beds. The next part of 39 ------- the hierarchy is really bringing all of that data together in a modeling effort on the regional basis. Trying to balance the various kinds of activities that can occur in a region against their effects on the Bay. Again, the herbicide issue is of prime concern. So, you might view the problem as what happens if you ban a herbicide like atrazine to the farmer. What kinds of cost does this cause? What cost will go through the economy? If a particular herbicide must be banned, we need to know what the costs and benefits will be to the whole society. Along with those hierarchies we plan to use mathematical modeling structure at each level so that we begin to bring higher and higher levels of realism as we go from the laboratory, where we can do controlled experiments very easily, to the field, where we cannot do very much in the way of experimental work at all. Our study is designed to balance the Virginia effort which is occurring mostly in high-salinity regions of the Bay, so that we have a whole synoptic data base which eventually we hope will give us better information on why Bay grass is declining. Dr. Robert Orth: Speaking for the Virginia Institute of Marine Science, Virginia's approach is threefold -- three programs funded by the EPA Chesapeake Bay Program. The first one concerns the dis- tribution and abundance of submerged aquatic vegetation in the lower Bay. Since the dominant vegetation in the lower Bay is eel grass, we are really looking at abundance and distribution of eel grass, using sophisticated techniques. There is a counterpart in Maryland, doing the same type of work. What we are using is remote sensing with aerial photography to get a better look at what has been done 40 ------- in the upper Bay and in terms of doing some spot sampling. So, we have used remote sensing in which you get a much better look of what is going on in larger areas. This is also being done in Maryland, by some people from the American University and Byrne Satellite Corporation. We are trying to look at the present distribution and will then focus on the historical aspects to see if we can correlate what has happened in the past with what is hap- pening today. The second study involves eel grass. We are looking at the biology, propagation and impact of herbicides. The basic biology of eel grass, surprisingly, has not received attention. There has been very little information worldwide, despite its abundance. We are going to look at some of its growth characteristics and how eel grass modifies its environment. One of the important things to remember is that grasses are very capable of modifying their envir- onment and can do so drastically. Characteristics that were there before the grass was there may be totally different after grass is established. What is happening when a grass colonizes an area? How are those characteristics modified and what can be done about erosion with and without vegetation? One of the unique thrusts in this pro- ject is that we are going to put a lot of emphasis on seeds. I call this unique because not very many people are working in terms of using seeds and seedlings to establish new areas. What I would like to do is establish a culture method, where we can go out and collect a large number of seeds, germinate them in the laboratory, and plant seedlings rather than take .the whole plants, which is a 41 ------- much more labor intensive project. Instead of taking plugs for transplanting, a technique where we could get very good germination of seeds, culture them in the lab, and get them out in the field where they can grow much more rapidly, we can perhaps plant larger areas. Vern can probably substantiate that. There is a lot of effort involved in terms of planting things underwater. We feel that much better techniques are possible for planting aquatic plants. Part of that project has to do with the impact of herbicides. There are relatively few data on the lower Bay so what I would like to do is try to establish some data for the lower Bay on levels of herbicides. We are also going to try to look at impact of herbi- cides on eel grass seeds and seedlings. Perhaps the seedlings are much more sensitive to levels of herbicides than adult plants and this may be critical in terms of the over-all Bay program. When do these seedlings germinate and if herbicides are around, either in sediment or suspended sediment, what affects do they have on plants in this seedling phase? One of the dominant ways eel grass is going to recruit is via seeds and seedlings. This third project is involved with the functional ecology and importance of eel grass beds. This will be coordinated with a re- lated project in Maryland. We will look at high salinity areas and what eel grass beds' role is in the Chesapeake Bay system. We are basically looking at the plant itself, the animals utilizing it, and exactly what role the grass plays. Does it serve as a refuge, or, basically, as a habitat for animals? Almost anyone will say if you go to a grass bed you will get more crabs than outside of 42 ------- the grass bed and a lot of studies have shown that there are some major migrations in and out of the grass beds between day and night which might indicate that the animals are basically using the grass as a refuge, to perhaps hide from predators that might utilize them during the day when they can be seen. A lot of the things found in grass beds are small juveniles, which indicates that the grass may be serving as a nursery habitat. There are at least six or seven of the major investigators at VIMS that are intricately involved in this whole program and these programs are coordinated with Maryland. We can look at really the whole Bay via these projects. Dr. Newby: We have just completed a degradation study in an estuarine environment. We have actual Chesapeake Bay water and Chesapeake Bay sediment and observed the dissipation of atrazine in the system over a three to four month period. What we conclude from this is that it behaves very similarly to the terrestrial system or fresh water system. We saw little difference, perhaps a decrease in kinetics. We also are supporting research to determine the route of atrazine uptake in aquatic grasses. We are trying to determine whether the leaves are the most affective route or the roots. Sus- pended sediment will be treated at rates approximating what David is reporting, allowed to settle onto the leaves and then the uptake is in the plant via this route will be determined. I have to inter- ject a comment on the large quantities of herbicides reported in the suspended sediment. Without arguing that point, a bit of reasoning leads me to believe that if the leaves are indeed as mucilaginous as 43 ------- I hear they are, then the affinity of atrazine to the mucilaginous material would be greater, I think, than the absorption into the plant itself. This type of research is in progress. We should be able, in a few months, to determine at least a route of uptake. We are also supporting research on the chronic effects of atrazine on several Bay grasses. We will have more data in the future. In addition, as you heard, we are cooperating with Mr. Stotts and his program by analyzing sediment and water and trying to determine if there is a correlation between dieback and no dieback in the presence of atrazine residue. As he pointed out, the Honga River has serious grass problems, however, we haven't yet detected any atrazine residue in the water or sediment. The Chester River, in which there is abundant SAV, is where we are seeing a small amount of residue in water. We are also planning to cooperate from the analytical aspect with Dr. Stevenson and Dr. Orth. That is the extent of our program at the moment. Dr. Munson: At the moment we are working up the analysis of the samples collected at the Harrisburg Station on the Susquehanna River. Our intent was to sample through a yearly cycle, and then use the herbicide data and the hydrological data supplied by the Geological Survey to work up a yearly budget for atrazine and sima- zine being carried by the River. That activity and the sampling in the Bay proper were performed at the Annapolis Field Office in support of the EPA Chesepeake Bay Program. These are separate activities. The Annapolis Field Office 44 ------- supports EPA Region III analytically and we have many programs to carry out. Herbicide research in the Bay does not normally fall within our mission. After we wrap up the samples we have now and write the report for submission to the Bay Program, we probably will assist the Bay Program in the following year. We may in a small way do some analysis in support of Vern Stotts' program as a sort of quality control effort. I am not prepared to comment in detail on the various programs that are being supported by the Chesapeake Bay Program. Most of the specific projects have been mentioned this evening. By way of general information, Richard Pepino of the Chesapeake Bay Program staff has provided the following information: The Chesapeake Bay Program Plan of Action entitled "Toxics Accumulation in the Food Chain" has incorporated several tasks that address herbicide concen- trations in the ecosystem. Task 1 - Baseline Monitoring for Toxic Pollutants: Under the scope of work for this task, herbicide sampling will occur in the water, sediment and biota in the main stream of the Bay and the tidal portion of its major tributaries. Task 2 - Source Assessment of Toxic Substances: This task is under current development by the Toxics Work Group. This task will attempt to develop a regional atlas of toxic sources that may inpact the estuary. The task will be developed in concert with other EPA and state programs. It seems likely that herbicide usage in the Bay region must be considered in the Source 45 ------- Assessment phase of the program. Task 3 - Fate, Transport, and Transformation of Toxic Substances: Herbicide concentrations will be determined in suspended sediment and fluid mud. These particular media are important indicators of pollutant movement in estuaries. By evaluating herbicides, as well as other pollutant levels, predictive models defining imput and transport within the ecosystem can be developed. Dr. McLain: I am going to make two very quick points be- cause I think the most important part of the program will be for questions from this fine audience. I want to stress the point I made earlier that although Bob Orth may be right about the his- torical pattern and the cyclicness of the Bay grasses, what we can do through seedling study is to iron out those peaks and valleys. We can help; we can make it recover. This is very important. Second, I would like to say that no more than three short years ago, very few people including those in this room had any idea of how important the submerged aquatic vegetation was to the health of the Bay and I think we owe a lot of thanks to the EPA for supporting this research. You can see that it is going to be very active. Dr. Fertig: I think if you don't realize it already, you are probably going to before the discussion is over, that what is making things difficult is the aquatic environment. It is a very complex situation, and I expect that if you had the opportunity to look extremely closely at a glass of water you might stop drinking. Dr. Cronin has been very effective in keeping me quiet because he keeps 46 ------- tying each question specifically to the Bay and our re- search program in the USDA doesn't happen to tie directly to the Bay. We do have a very extensive research program in connection with the aquatic environment at many locations around the country and I think there are and will be princi- ples that will fall out from our studies. I encourage the researchers involved with the Bay to follow the results of these programs closely. I feel that, because of the complex- ity of the situation and our interest in a quick solution to the problems,that we have tended to start in the middle,and as a result the loose ends are beating us to death. What we need to do is go back to a few more basics of the situation in relation to ecological principles and other aspects associ- ated with the Bay. This means that we will come closer to an answer to our problems; and then, we should concentrate heavily on the programs that are being discussed. Dr. Correll: We are currently carrying out two activi- ties. One of them is a field oriented plan to gather data at specific stations in the Bay. We look at habitat factors which affect the ecology of plants; things like salinity and temperature and bottom characteristics, some of which don't change in the beds of plants. Then we are looking at shading factors - things that interfere with sunlight reaching the plants -- and herbicide factors and we are trying to relate any of these three groups or all of them to plant populations at these selected stations. It is not an attempt to survey 47 ------- the plant populations in the Chesapeake Bay. It is an attempt to relate these factors to what happens in specific places. That is the field activity and we hope to find out this year what happens in a relatively wet year compared with the rela- tively dry years we have had in the last two. The laboratory effort last year did some bio-assays and is being conducted again this year under a different set of conditions. We are trying to expose the plants to stresses such as salinity which they experience in the Bay naturally. Most of these plants outside of eel grass and widgeon grass are stressed by salt and all can be stressed by light inten- sities which might be suboptimum or by natural temperatures which might be above what they really like. We are picking a set of stresses that are reasonable but occur widely in the Bay and then we are going to dose plants with herbicides under those conditions. Various combinations of herbicides will be used. This time we want to simulate run-off by dosing them with sediments that have been charged with herbicide and dumped into the tank in reasonable concentrations. We have one other new effort that is going on now. We have set up some large saltwater tanks and planted them with six species of Bay grasses. We have an instrument set up so that when we had a thunderstorm recently, we could divert storm run-off into one of these tanks. We have a control that we gave a similar load of suspended sediments from a forest where there wouldn't be any significant amounts of herbi- cides present. That isn't over yet; but it is another experi- 48 ------- ment where we can link conditions between the lab situation and a Chesapeake Bay situation. Chairman: I recently went to a data conference where they talked about handling enormous quantities of data. The best one-liner I heard there was when someone said his boss asked him to get everything together about a particular topic and he gave him a computer printout, then a summary, then an abstract, then amendments to that; and the boss said, "Stop! I cannot drink from your fire hose!" Before we become a fire hose, I am going to defer the last question on our list, future research needs. It has become obvious that a great deal of important effort is being directed to the question of relationships between herbicides and plants. I am not sure that anyone is capable of judging further research needs until we have an opportunity to see what is accomplished in present efforts. I want to get back to the audience. So I now invite questions or comments from the members of the Citizens Steering Commi ttee. QUESTIONS AND ANSWERS Dr. Bauereis: Dr. Cronin will remember the recent meeting in Mt. Pocono. We asked a panel of scientists if they thought things were either good or bad and it had to be answered on the basis of opinion because they couldn't answer on the basis of data. Now I am asking you the same question: Do you think it is predominantly herbicides causing these problems? 49 ------- Dr. Corre11: I think scientists as a whole resist questions like that. I don't want to say what my opinion is. You can correlate things, saying something happened and at the time something else happened. But that doesn't prove that the first thing that happened caused the second thing to happen. All we have at present are very few correlations in time between plant die-offs and other events and some very incom- plete data sets and I think it would be very misleading and probably detrimental to speculate. That is my opinion. Dr. Fertig: Based on the information that I have been able to see, and the information that I think we have available from the program, I do not believe that the problem can be directly attributed to herbicides. Dr. McLain: My feeling, intuitively, is that it is not pre- dominantly herbicides. Intuitively. Dr. Munson: The data convince me that there are trace levels of herbicides occurring in the Bay, presumably running off. from the fields. That I am convinced of. But I really cannot form an opinion based on the existing data as to whether herbicides are effecting aquatic vegetation or not. Dr. Newby: My feeling is that the data we have would not support the conclusion that herbicides are affecting SAV1s. Dr. Orth: After looking at some of the historical records here that I have talked about, my opinion would be that it is not having any affect at all; but, we must have much more data. 50 ------- Dr. Stevenson: I think there is enough data to set up an hypothesis and that's good for experimental work. I don't think by any means that the hypothesis that herbicides are responsible for the decline of Bay grasses is proven one way or the other. It is my personal inclination that herbi- cides may be important in some areas of the Bay, possibly along with some other factors. This is what we said in our literature review which should be available this fall from the U. S. Fish and Wildlife Service, the Chesapeake Research Consortium or the University of Maryland Center for Environ- mental and Estuarine Studies. Mr. Stotts: I hope that it is not herbicides because the no-till method of farming has so many good methods about it. If we can reduce the amount of sediments that flow into the Bay and if no-till is used to its best advantage, we can knock out one of the factors that is reducing the grass in the Bay -- the reduction of light. Dr. Parachetti: I concur with the last four speakers. Dr. Fertig: I would like to make one further comment'. From 1965 to 1976, I spent all of my time screening for herbicidal activity. On the average, 100 to 150 compounds per week were screened to find ones that would have ill affects on aquatic plants. I have been totally amazed at the ability of those plants to survive a lot of things I thought would get them including atrazine, linuron, alachlor and trifluoralin. They are much more durable than I expected. I think one of the major problems we have in developing good research programs 51 ------- reflects back on what David was talking about -- finding a medium in which you can grow aquatic plants effectively. Chairman: I think that the shadows are serious enough in what we have heard and I think that the two efforts we are relating here, agriculture for the production of food and fiber and the Bay and its service to a great many of us, are both of such high importance that we must clean up the shadows. I think it is exceptionally important that competent, adequate research be done to clear up the uncertainties in this matter. I can't see that this has been the cause of widespread damage but the shadows are there. I don't want farmers blamed for what is not their fault. On the other hand, if they are having a signifi- cant effect, we need to know it, they need to know it, and everyone else needs to know it. There isn't any way to brush it aside without adequate information. Mr. Morgan: I hate to see a Department of Agriculture man so complacent, but he mentioned one thing about the "ends" that were at odds with each other and I am one of those ends. I happened to know that an oyster hatchery cannot operate where there are pesticides present. I know that one teaspoon of the herbicide we are talking about will kill a hundred thousand larvae in a tank overnight. I don't know what it does to Bay grasses; this is not in my field. I do know that all of the pesticides will kill oyster larvae. Somebody here today mentioned Dr. Butler's 96-hour bio-assay. We are talking about adult oysters. All larvae are killed by nearly all of the chlorinated hydro- 52 ------- carbons. Anything that will kill oysters will kill a million other organisms. I think that the study done at Rhode River clearly indicates that it should be finished. It clearly in- dicates that the Department of Agriculture would love to be absolved from any complicity in the destruction of the Bay's ecology. I feel that they have too long ignored the problem. We are a smaller industry, but we do exist. We are part of the food protein "chain and would like to see it continue. So I would like to see this research continued. The cyclical part that Bob mentioned is not necessarily true. I have oyster grounds. When pesticide levels rose in the Rappa- hannock, we lost our grasses. The study there was discontinued on pesticides ten years ago. I would like to see more detailed work. The real conclusion you are going to have will possibly not have atrazine or any one particular item. In the monitoring of Kepone, things they were clearing out of their gas chromato- graph columns were a lot more important than Kepone. There is enough in our waters to frighten me, not necessarily all one mild herbicide. So I think that we need a total toxic program. To continue the herbicide programs is extremely vital because I don't be- lieve anyone wants to hide away from the facts and ignore them. There are many other ways to keep our farmer in his high pro- ductive level and science is now tackling it. We are yet to explore the many ways of contour farming in ditching adjacent streams, that could be done in many areas. We need a speaking 53 ------- communication with our Department of Agriculture friends that we haven't had in the past. Reports from the Department of Agriculture have come very slowly. It took us from 1948 to 1974 for Hardin to say, "Yes, there is a DDT. Yes, it may be dangerous." We have to go faster than that. However, I am delighted with our EPA program. I am delighted that we have somebody here tonight and I thank you all for coming and the Citizens' Steering Committee hopes that this type of meeting can continue to be productive, as I know this one has, and I would like to thank the panel. Chairman: Are there questions or short comments from the audience? Mr. James McFadden: I have been promoting no-till farming for a good many years and I can tell you that Dr. McLain got my atten- tion tonight when he mentioned it. Then this gentleman over here made me feel so good about it that I feel like making a couple of comments. I am a little surprised; it really hasn't come out about some of the specific work that has been done right here on the shore. Soil conservation has shown that under conventional methods for corn you get eight or nine tons of silt washing off in a year, where under no-till you get a ton or less. Those re- sults are consistent. As Dr. Correll said, this silt seems to be one of the guilty parties and just look at how you cut it down with no-till. Then you mentioned dust. Well, anyone who has ridden down the lower part of the Shore in the spring of the year or in late winter 54 ------- has experienced those dust storms that we have, even up in this part sometimes. When you have that mulch on the ground you have very little dust. So it seems to me like it might be in order to get some grant money to promote no-till. Then I want to comment on one thing this tall, blonde fellow from Virginia said. I have a hobby of teaching children to water ski; this summer I taught my 27th little boy how to water ski, in that Langford Bay area, and low and behold, there's acres of milfoil. It hasn't been there for eight years and now it is so thick youn can't get a boat through it. At dinner last year I commented on this and several people living along the Chester River said it seems to be coming back and thus substantiated what Mr. Orth was saying. You might think I am biased, but I really feel good about people of this quality that are interested in the Bay. You know, we all love it whether we are pesticide salesmen, farmers, or whatever. We love the Bay. A gentleman from Campbell's soup was telling me last night that EPA is going to come up and put a trap of fish below their plant down Morgan Neck to see if the fish would live or die. Then they were going to put a trap above that. He waited until noon time and they didn't come, so he called and asked if the man was coming and he said the fish had all died. What if they had put those fish over there before they died? Something else is wrong with those fish. It is very hard work. It is frustrating work and I really feel good that people are concerned about it. Because in the final analysis, our Creator and our posterity will judge us on the kind of stewards we are to the Bay and the land and things we have in our hands today. 55 ------- Dr. Andrew McErlean: It seems to me some of the commentary has gone to "What do we do now?" I think I would like to step back from that and see how we got to this point here. I have read that the year of first public use of simazine was 1958; for' atrazine, 1959; for diquat, 1962, for paraquat, 1966; and a whole list of others. The question I would like to pose is this, "Is there something wrong with the testing or the registration pro- cedure and the simplistic view that you can just dump anything that is good?" I don't .Like the sentiment that was expressed that everything that we do is good, and there is an unlimited amount of resiliency in the environment. I wonder if the panel would care to comment on the responsibility of the various agen- cies with respect to the testing, licensing, use and efficiency of these materials before they become a major problem as they seem to be now, or we would not be here discussing this. Thank you. Dr. Newby: It takes about eight to ten years from discovery to registration of pesticide by EPA. We probably test pesticides more than the pharmaceutical industry tests drugs. We know what happens to the compound from the standpoint of target plant meta- bolism; the fate of the compound in the soil; environmental mo- bility; and the effects in the aquatic environment. We try to determine the mechanisms of degregation, i.e., chemical, photo- lytic, hydrolytic, etc. Research is conducted on its effects on microbial populations in the soil; effects on microbial functions; and the effects of microbes on the pesticide. That's only part 56 ------- of it. We do residue studies on the target crop, probably 20 or 30 studies around the country, to determine what the pesticide residue levels are: We conduct toxicology studies long-term studies in rats, mice and sometimes in dogs; short-term studies in other animals and organisms. In reference to this particular subject of the Bay, we may have been negligent in the past by not considering what happens in an estuarine environment. We are looking at this more closely now. We had not anticipated that pesticides would be entering the Chesapeake Bay. We have learned something over the years that is both good and bad, as everyone else has. Dr. Parochetti: The responsibility for registration of pesti- cides lies with the Environmental Protection Agency which took it over from the USDA in 1972. If I am not mistaken, we probably have the most rigorous standards in the world; perhaps West Ger- many may be a bit more strict than us. But the responsibility lies with the Environmental Protection Agency. Dr. McErlean: Do you consider the registration procedures ade- quate? Dr. Parochetti : We may have the best system in the world. It may not have been adequate because we can go back and see we made a mistake with DDT, radiation, etc., but we didn't know. I respect EPA for their criteria by which they evaluate. They are in the process of re-registering every pesticide now. What 57 ------- we know now may not be adequate five or ten years from now. As long as EPA operates, we will probably continue to receive more requirements for registration of pesticides. Dr. Suzanne Bayley: I have a question that I guess relates more to management in terms of the sediments. It is apparent that the herbicides that come in small amounts probably do come in on sediments. It is also apparent that sediments are reduced in terms of no-till agriculture. What potential do you see for man- agement through the 208 programs or techniques that farmers can use to minimize those small amounts of herbicides that may come in on suspended sediments. Dr. Parochet ti: As someone indicated a few moments ago, land management, crop rotation, contour farming, all of these aspects are a part of the program. Some land situations adapt themselves better to certain types of farm operations than others. I think the Soil Conservation Service, along with the Land Grant Colleges, have a lot of active programs underway and that farmers are doing a good job in accepting these programs, where they can be adapted to their conditions. They may continue to do more, and I hope they will if they can. Certainly the no-till situation is an ex- cellent example of reducing the loss of sediment off of agricul- tural land. There just has to be a certain amount that cannot be stopped, unless you can stop it from raining. Dr. Bayley: Sediment isn't necessarily highly associated with a large percentage of material, am I correct? 58 ------- Dr. Munson: The point was that it appears that in a given volume of raw water out in the Bay the largest portion of the herbicides is in the dissolved fraction. Dave's data seems to indicate that, if you look at the particulates (suspended parti- culates, fine clays, organic coating, or wherever they are), you will find atrazine there, and the concentrations on particu- lates are rather high. But more of the atrazine in runoff is in the dissolved portion than actually adheres to sediments because the volume of water is large. We are saying that we must know more and understand more before we can apply the best possible technique to precluding the release of pesticides and herbicides into the system. Dr. Correll: The bulk of the herbicides coming off the fields comes off in solution. That does not mean that a significant amount does not come off on particulates. When they get into the Bay, the conditions are different. Just because an herbicide is bound to a given clay particle or in solution when it comes off doesn't mean it stays there. They are in equilibrium, and the change of conditions changes distribution. You have to keep straight whether you are talking about in the Bay or in run off or in the field itself. These are different situations. Our data in Bay waters indicate that over half of the herbicides are bound to suspended sediments. It is true that if you cut down on erosion you will probably cut down on the load coming off. To what extent is a little difficult to say. Voice: Are we saying that the atrazine is actually in soluliun 59 ------- in the water? Dr. Newby: Yes. There is atrazine in solution in the water. The total quantity of it would be more than what you would see in the sediment. The concentration on the small particles is great, but the total amount in solution in a given volume of water is greater. Mr. Herb Ward: The Elk River, is absolutely grassless at this point. It is, also, fishless. We usually have rather large schools of menhaden; we usually see them in the evening in calm water. We have almost none at all now. I noticed in the testing stations on the charts here that there were no samples taken in the Elk River and I would like to suggest that maybe there should be. In this way, we would get some idea of what is coming into the Bay from the Delaware River. According to the watermen on my staff, 80% of the time water is leaving the upper bay, and we are losing fresh water from the Susquehanna, into the Delaware. The other 20% of the time, the water is coming in from the Delaware. The water is going out through the Canal and coming up the Elk River. Its source is the Susquehanna. This would explain to me why we cannot get any good water into the Elk River because it is either laden with the pesticides coming from the Susquehanna, or it is coming from the Delaware where God knows what is coming in. I would also like to point out a correlation which I realize is not scientifically sound from a data point of view, but up where we are there is no grass hardly at all, but the concentration of pesticides is the highest. 60 ------- Ms. Penny Chalkley: Most of the discussion tonight has been about the herbicides and pesticides relating to agricultural activities. I wonder if anyone can give me the role of herbicides and pesti- cides as used by homeowners, municipalities, local governments, etc., in this picture. Dr. Parochetti: From the standpoint of insecticides in connection with the homeowner, you have whatever household pesticides that might be involved. Or whatever insect pesticides might be used in connection with the lawn. Fungicides for disease control might be used with the home garden or the lawn. Herbicides are used for weed control in the lawns or the ornamentals such as flowers. That would be a granular rather than a spray product. I suppose that there is a feeling that the homeowner is probably the more guilty one in the safe use of pesticides. That is partly due to the types of equipment for application. There are the types that are hooked to the garden hose and sprayed and you have the knap- sack. If there is a misuse by the homeowner, it would be associa- ted with the ability to apply it. Mr. Ronald Johnson: I am Director of Plant Industries, Maryland Department of Agriculture. One of my functions includes the pesticide applicators law regulating the use and application of pesticides. Gene is very familiar with our program inasmuch as he was chairman of our Pesticide Advisory Board for a number of years. Albert Sanderson was also a member. Several years ago, when Maryland had its own list of restricted use pesticides, we had fairly accurate records of the amount of pesticides used not 61 ------- specifically by homeowners but in the metropolitan area, Baltimore and Washington. This was because we required each user, or pur- chaser of a restricted use of pesticide, to get a permit from the Department for the amount of pesticide that they intended to use. There were about 18 or 20 restricted-use pesticides at the time. It included the chlorinated hydrocarbons, TEP, parathion, 2,4-D and things of that nature. The last figures we had were for 1975- 76, but at that time the majority of applications was coming from the urban area, Baltimore, Washington. As best I can remember, the figure was something like 85%. I would also like to comment on the earlier question about the current safeguards for pesticide use. Comments have already been made about the requirements that companies have to go through to test a pesticide to get it through EPA. Once a pesticide is regis- tered by the EPA, to use it in Maryland it must also be registered by the State Chemist's Office, the Department of Agriculture, and then commercial applicators in Maryland must be certified by my division as being competent to use. We have several thousand applicants for certification. They are required by the State and Federal lav/ to take a written exam to become certified. It is not a perfect system, but it is a far better system that we had several years ago. It will improve as we go along. Also, private appli- cators who use restricted pesticides must also be certified. Currently, we have between eight and nine thousand private appli- cators certified in the State. These are basically farmers, by definition, by State and Federal law. The point I am making is not that we have a lot of people applying pesticides, but that we have taken some steps. They must either take specific training 62 ------- or take a written examination. They are improving their abili- ty to apply pesticides safely. We don't know that everybody in the State is using pesticides safely and effectively, but at least they are probably using it more correctly in terms of the amount, the timing, the right pesticide for the right pest, etc. It should go a considerable ways toward eliminating some of the problems that exist or are speculated to exist. Mr. Jack Witten: I am from the Potomac River Association and I would like to make one suggestion and two observations for fu- ture work. It seems to me that there needs to be some more work done on the effects of herbicides on infant species. Look at the chemi- cal soup coming down the river in terms of the synergistic values; there has been some reference made to this today. One of our investigators counted the number of television sets, which are loaded with PCB's, by going into the sanitary landfill of our District of Columbia. Ultimately, the residual of that and all the other stuff is put in that sanitary landfill, which is neither sanitary nor land. There is a very interesting area of investi- gation that needs to be done. I have looked at some of them and because when you scoop dirt up to cover the trash you want the bottom to be dry, they scoop out a ditch down the water course so that what runs out of that landfill will run away so that they can get their earthmoving equipment into the bottom of it. I am sympathetic with the farmers. I have a chance to ob- serve them every day. St. Mary's County has the fourth largest dollar value of agricultural products in the Potomac River Basin. 63 ------- I would like to suggest another avenue of investigation in that most of our fields are bordered by roads. With our super highways and road construction, these things are forming conduits which convey what comes off the road and what comes off the field and concentrates the volume and increases the velocity. It would seem to me that rather than beat on these farmers, many of whom are rather marginal economically today, we ought to look at the institutional opportunity of doing something about the way we treat roadsides which drain these fields and concentrate the run-offs and increase its volume and velocity. Presumably state roads, bureau of public roads, and other people have both the resources and knowledge to do something about this and are eco- nomically equipped. Perhaps we can start working on this prob- lem first and then after we have licked that one then go to the farmers. I'd like to suggest that as an avenue of investigation because I feel that these highway systems are secondary streams of the wrong kind. Dr. James Miller: I am from the Agronomy Department of the University of Maryland. I appreciate very much the panel getting together this evening and relating to us the information that is available. As I have listened this evening to this information, I have been puzzled by some of the things that come to me. For example, I heard one of the members mention the fact that the Chester River has many grasses growing. I look at the Chester River, and I am very well acquainted because I originally was a native from that country, there is much agriculture going on in that area with corn and soybeans. The question is, "Why do we 6.4 ------- have the grasses growing in that river if the herbicides are causing the damage from run-off from agriculture?" Then, of course, we have other rivers where we do not have the grasses growing. I think we really need to look at this problem in more depth, and the panel has pointed this out -- there could be a combination of things. We have talked about cycles that exist over a period of years where the grass population goes up and down. I think that we scientists working in this area have to find the total truth and all the facts before we start jumping to conclu- sions that the problem might be herbicides, it might be turbidity, or whatever. I think we are at a stage where we cannot point out that it is a given problem that is creating this situation. I think we are on our way in this investigation as far as the grasses in the Bay and I think a lot has been accomplished in the last couple of years. But I think we have to go a ways, too, and I think there are a great many questions to be answered yet. Ms. Ajax Eastman: I am with the Maryland Conservation Council. I am somewhat surprised that I don't see anyone from the Mary- land Forestry Department here tonight. I think that dioxin is a herbicide also ana i tninK tnat tney would be interested in finding out what the researchers have to say about that. At the risk of opening another can of worms, I would"1 request that maybe that type of herbicide would be looked at also and its use in the state. Dr. Fertig: The only comment I would make is that, in connection with dioxin, it primarily relates to the herbicide 2,4,5-T which 65 ------- is the one used for woody plant control in forestry and other areas. Dioxin itself does not have herbicidal activity. It is a contaminate of 2,4,5-T in the manufacturing process and there are a lot of studies being conducted at the present time. There is a lot of interest all over the country in the dioxin question. EPA has issued the Rebuttable Presumption Against Registration (RPAR). This requires a very close study, assess- ing the risk associated with 2,4,5-T regardless of whether it is used in forestry, on range land, on right-of-way or elsewhere. This study is underway at the present time, and is being assisted by groups all over the country, including industry, the Depart- ment of Agriculture, state experiment stations, user groups, and all kinds of interested environmental parties. Since the issu- ance of the 2,4,5-T RPAR on the 6th of April, we have had within the Department of Agriculture, at least 500 letters emphasizing the importance of making a very close study of this particular compound and the contaminant that is in it. Dr. Correll: I want to comment on an earlier comment. When it comes to other kinds of herbicides, we have only discussed a couple today, and there are many herbicides in use. Home owners are not using the herbicides that we discussed today, but they are using other herbicides. The highway department, power com- panies, and lots of other people use herbicides. They are not using the same ones we have discussed tonight and as far as I know, nobody is measuring the impact of these on the Chesapeake. There is a technical problem in that each of these compounds or groups of compounds has to be analyzed by a different technique. 66 ------- It is very expensive. This is just a starting point. We have begun looking,at least in our own work and some of these other studies here,at the ones that we know are being used very widely and are most likely to be a problem, but they are not by any means the only herbicides. Dr Newby: I would like to ask a question, to one of the water quality people perhaps. Can anyone give me an indication of the number of compounds that have been identified in the water to date? I just wondered if anyone has a fix on this. We are talking about a large number of compounds. Chairman: On this question of herbicides and aquatic vegetation, I suggest that a top-flight technical committee be established among the EPA, U.S. Department of Agriculture, U.S. Fish and Wild- life Service, the states, and at least two external people of un- impeachable quality from outside of the area. Ask them to design the research program which will nail this thing clearly and finally. Ask them to agree that they will endorse the product if these pro- cedures are followed properly. And ask their agencies to provide support for the research. We have used such technical committees occasionally in the past and they can be effective. Thank you very much indeed, you have been a splendid group for three to three and a quarter' hours, and we appreciate it. 67 ------- |