Environmental Protection
                                  Office ot Pesticioes ana
                                  Toxic Substances
Fall 1990
 National  Pesticide  Survey

What is
How Does 4-
Behave in
Soil and
How Doe* 4-
Get into
     The U.S. Environmental Protection Agency (EPA) has completed its five-year
National Survey of Pesticides in Drinking Water Wells (NPS), a study of the presence
of 127 pesticides, pesticide degradates, and nitrate in community water system (CWS)
wells and rural domestic drinking water wells.  4-Nitrophenol,  a component of ethyl
and methyl parathion pesticides, was delected in the Survey.  Because testing of 4-
nitrophenol did not yield quantitative results, EPA does not have specific information
about.the concentrations of this contaminant in drinking water wells. This fact sheet
provides a description of 4-nitrophenol, its potential health effects, and guidance on
both treating and preventing well contamination.

     4-Nitrophenol is a degradation product of insecticides from the chemical famiry
of mononitrophenols.  4-Nitrophenol was registered for use in 1948.  Insecticides that
produce 4-Nitrophenol include ethyl and methyl parathion. 4-Nitrophenol is used in a
wide range of applications on many crops and against a variety of insects, such as
aphids and mosquitoes. Pears and apples are some of the crops treated with

     The behavior of a pesticide after it is released to the environment is dependent
upon its movement in air, water, and soil as well as the rate at which it is transformed,
or broken down.  Pesticides applied to crops or the soil surface may volatilize
(vaporize) to the atmosphere, be carried off by surface runoff, be carried to ground
water through leaching, or remain in the soil through adsorption (adherence) to soil
particles and undergo little movement in air or water.  Pesticides may be transformed
by reaction with water, microorganisms, and exposure to sunlight. The likelihood that
4-ftftrophenol will migrate into ground water is influenced by its tendency to be
transported (move) from soil to air and water and to be transformed by these various
processes,  as well as by the characteristics of the site, such as soil type, moisture,
temperature, and depth to ground water. 4-Nitrophenol has a high potential to be
transported, and a medium potential to be transformed.

     4-Nitrophenol migration Into ground water could result  from agricultural and
other applications  of parathion pesticides on cropped land. Other non-agricuituraJ
applications of parathion pesticides may cause contamination in ground water. 4-
Nitrophenol could  also reach the soil from direct entry into a well through accidental
       «piiis or improper storage near a well.
NPS 4-Nttmph9nol

Findings of
the National
What Health
Effects Might
be Caused by
In Drinking
How is Water
Treated to
How Can
tion be
      The presence of 4-nrtrophenol was detected in both CWS well and rural
domestic well water samples. The analytical method selected for detecting the
presence of 4-nitrophenol. is not reliable for measuring concentrations of 4-nitrophenol
in water samples. Because the presence of 4-nrtrophenol cannot be confirmed with a
high degree of confidence, national estimates for the number of wells containing 4-
nitrophenot would be highly unreliable and therefore are not provided here.

Non-Cancar Effects: EPA has set a Lifetime Health Advisory Level (HAL) for 4-
nrtrophenol in drinking water at 60 ^g/L Lifetime HALs represent the concentration of
a contaminant in water that may be consumed over an average human lifetime without
causing adverse health effects.  Lifetime HALs are based on health effects that were
found in animals given high doses of the pesticides in laboratory studies.  This level
includes a margin of safety.  Consuming 4-nitrophenol, however, at high levels well
above the Lifetime Health Advisory Level over a long period of time has been shown to
result in adverse health effects in animal studies, including damage to the liver,
respiratory stress, and gastritis.

Cancer R!*k:  Data from laboratory studies are inadequate for EPA to determine if 4-
nitrophenol can increase the risk of cancer in humans.

Standard: EPA sets enforceable standards for public water systems, called Maximum
Contaminant Levels (MCLs). These regulatory standards set achievable levels of
drinking water quality to protect human health.  EPA has not established a MCI for 4-
nitrophenol, but plans to list 4-nitrophenol on the Drinking Water Priority List for future
MCL consideration.

      4-nitrophenol can be detected in drinking water by a laboratory using an EPA
method such as #515.1. If 4-nitrophenol is detected in well water and confirmed by
retesting to be above 60 pg/L State or County health officials should be consulted.
They may advise periodic retesting to get an accurate overall picture of  the water
quality because changes in seasonal precipitation and changes in pesticide use can
cause variations in the amount of chemicals found in water wells.  They  also may
advise using an alternative drinking water supply (bottled water is an example of a
temporary alternative), treating the water, or drilling a new or deeper well.  If you
receive your well water from a community water system, and are concerned about the
quality of your water, contact your State public water supply  agency.

      You may also be able to treat your well water to remove pesticides and other
contaminants. Treatment by granular activated carbon adsorption can remove 4-
nitrophenol from water.  However, this technique is not necessarily appropriate or
available in every situation. Your State or County health officials should be able to
provide advice on the best approach to follow.

      Several steps may be taken to prevent pesticides or nitrate from entering wells,
such as eliminating direct entry through the well wall, drilling a new well, or modifying
or reducing pesticide and fertilizer use.

Ellmlnata Direct Entry Through the Wall Wall

      If pesticides or nitrate are  present in well water, they may be entering the
ground water through the well itself rather than through the soil.  If the well is old or
poorty constructed, or if there are visible cracks in the well casing, obtain expert
advice on whether or not improvements can be made to the well.  In addition,
investigate simple methods of capping the well or sealing it at the surface to prevent
entry.  Do not conduct any mixing activities near the well if you use well water to mix
pesticides,  because a spill could lead to direct contamination of the well.
                                                                                    rtTS 4-Nttroph»nol

                  Drill a New Well
Why was the
Where to Go
for More
      If the soil surrounding the well is the source of contamination, drilling a new or
deeper well may make sense if water can be drawn from a deeper, uncontaminated
aquifer.  Unfortunately, it often is difficult to know the quality of the ground water
without drilling or extensive testing. Seek expert advice before you drill.

Learn More about Pesticide Ute

      If you use pesticides, whether for agricultural or home lawn and garden
purposes, you should consider attending training courses given by your State or
County agriculture department on  how to reduce activities that can contaminate
ground water. You may find that you can eliminate or lessen the frequency or quantity
of your pesticide usage by choosing alternative methods of pest control.

      EPA conducted this survey to determine the frequency and concentration of
pesticides, pesticide degradates, and nitrate in drinking water wells nationwide and to
examine the relationship between the presence of pesticides in drinking water wells
and patterns of pesticide use and  ground-water vulnerability.  The Survey sampled
566 community water  system wells and 783 rural domestic wells for 127 pesticides,
pesticide degradates,  and nitrate.  The wells were selected as a representative
statistical sample to provide nationwide estimates of the presence of pesticides and
nitrate in drinking water wells,  and are  not meant to provide an assessment of
pesticide contamination at the iocal, County, or State level.

      This fact sheet is part of a series of NFS outreach materials, fact sheets and
reports.  The following additional fact sheets are available through EPA's Public
Information Center (401 M Street SW, Washington, DC 20460, (202) 382-2080):
                  Survey Design

                  Survey Anttytes

                  Quality Assurance/
                  Quality Control
                            Analytical Methods

                            Summary Results

                            Fact Sheet for each
                            detected analyte
Project Summary


How EPA Will Use
The NPS Results
                       Additional information on the Survey and on pesticides in general can be
                  obtained from the following sources:
                  U.S. EPA Safe Drinking Water Hotline
                  1-800-426-4791 (In Washington, DC (202) 382-5533)
                  Monday-Friday, 8:30 am to 4:30 pm Eastern Time

                  National Pesticide Telecommunications Network
                  24 hours a day

                  U.S. EPA Office of Pesticide Programs (OPP) Docket
                  Public Information Branch  (H7506C)
                  401  M Street, SW
                  Washington,  DC  20460
                  Telephone:   (703) 557-2805
                                                  Information on regulation
                                                  of pesticides in drinking

                                                  Information on health
                                                  effects and safe
                                                  handling of pesticides

                                                  Background documents
                                                  for Survey (available
                                                  for review)
NPS 4-NKmph»nol

                  National Technical Information Service (NT1S)          Copies of the
                  5285 Port Royal Road  .                             NFS Phase I Report
                  Springfield, VA 22161                               (available 1991)
                  (703) 487-4650                                     and
                                                                    NPS Phase II Report
                                                                    (when available)

                        If you are concerned about the presence of pesticides and nitrate in your
                  private water well, contact your local or State health department.  Other experts in
                  your State environmental agency or agriculture and health departments may also be
                  helpful to you.  If you receive your drinking water from a community water system and
                  have questions about your water quality, contact your local community water system
                  owner/operator or the State water supply agency.

Bibliography    U.S. Environmental Protection Agency. Drinking Water Health Advisory.  Pesticides.
                  Michigan:  Lewis Publishers, 1989.

                  U.S. Environmental Protection Agency. Drinking Water Regulations and Health
                  Advisories.  April, 1990.

                  U.S. Environmental Protection Agency. Health Advisory Summaries. January 1989.

                  U.S. Environmental Protection Agency. Pesticides  in Drinking  Water Wells, September

                  Worthing, Charles R., ed.  The Pesticide  Manual. 8th ed. Thornton Heath: The British
                  Crop Protection Council, 1987.
                                                                                    NPS 4-Nttrophinot