vvEPA
United State*
Environmental Protection
Office of Water
(MC-4304)
EPA-822-F-93-002
October, 1993
Fact Sheet
Ambient Aquatic Life Water Quality Criteria
for 2,4-Dimethylphenol
AUTHORITY
Ambient water quality criteria are published pursuant to Section 304(a) of the Clean Water
Act and may form the basis for enforceable standards if adopted by a State into water quality
standards. The criteria reflect the latest scientific knowledge on the identifiable effects of
pollutants on public health and welfare, aquatic life and recreation. They are developed
using a process described in the "Guidelines for Deriving Numerical National Water Quality
Criteria for the Protection of Aquatic Organisms and Their Uses" (Stephan fiLaL, 1985).
BACKGROUND
2,4-Dimethylphenol (2,4-DMP) is a naturally occurring, substituted phenol derived
from petroleum or coal tars. 2,4-DMP (l-hydroxy-2,2-dimethylbenzene, m-xylenol, 2,4-
xylenol or m-4-xylenol) is used in the manufacture of phenolic antioxidants, disinfectants,
solvents, pharmaceuticals, insecticides, fungicides, plasitcizers, rubber chemicals
polyphenylene oxide, wetting agents, and dyestuffs. 2,4-DMP is also an additive of
lubricants, gasolines, and cresylic acid. 2,4-Dimethylphenol is classified by EPA's Office of
Water as a priority pollutant (Section 307(a) of the Clean Water Act).
Acute and Chronic Criteria for 2,4-dimethylphenol in this draft document will .
supersede guidance given in the previous Ambient Water Quality Criteria for 2.4-
dimethvlphenol (U.S. EPA, 1980). These new criteria were derived using improved
procedures and additional (more current) information.
concentration (i.e., acute exposure)
does not exceed 1,300 ugA more
than once every three years on the
average, and
saltwater aquatic organisms and
their uses should not be affected
unacceptably if the four-day
average concentration (i.e., chronic
exposure) of 2,4-Dimethylphenol
does not exceed 110 ug/1 more than
once every three years on the
Except where locally important species are
very sensitive.
* freshwater aquatic organisms and
their uses should not be affected
unacceptably if the four-day
average concentration (i.e., chronic
exposure) of 2,4-Dimethylphenol
does not exceed 530 ug/1 more than
once ever/ three years on the
average and if the one-hour average
-------
average and if the one-hour average
concentration (i.e., acute exposure)
does not exceed 270 ug/1 more than
once every three years on the
average.
IMPLEMENTATION INTO STATE
STANDARDS
Ambient water quality criteria may form
the basis for enforceable standards if
adopted by a State into water quality
standards. States may opt to develop site
specific criteria (Water Quality Standards
Handbook, December, 1983, EPA#:
440/5-83-011). Replacement of national
criteria with site specific criteria may
include site specific criterion
concentrations, mixing zone considerations
(Water Quality Standards Handbook,
December, 1983, EPA#: 440/5-83-011),
averaging periods and site-specific
frequencies of allowed exceedences
(Guidelines for Deriving Numerical
National Water Quality Criteria for the
Protection of Aquatic Organisms and Their
Uses, Stephan fl aL. 1985). When the
basis for site specific criteria relate to the
averaging period, there should be a
justification for why variability
assumptions underlying national criteria
are inappropriate.
AVAILABILITY OF DOCUMENT
Copies of the proposed criteria document,
and other referenced documents, may be
obtained from the address below.
2,4-Dimethylphenol Proposal
Water Resource Center, (RC-4100)
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C., 20460
For further information please contact:
Mrs. Amy L. Leaberry
U.S. Environmental Protection Agency
Office of Water
Water Quality Criteria Section
(Mail Code - 4304)
401 M Street, SW
Washington, DC 20460
------- |