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Water Contaminant Information Tool

A one-stop reference tool for contaminants of concern for the Water Sector

The Water Contaminant Information Tool

(WCIT) is a secure online database comprised of
comprehensive information about chemical, biological and
radiochemical (CBR) contaminants of concern for the Water
Sector. WCIT provides drinking water- and wastewater-
specific data from peer-reviewed sources and research in a
one-stop, easy-to-use tool. WCIT's functionality and content
were shaped and validated by water utility professionals,
scientists and public health experts. The purpose of WCIT
is to assist drinking water and wastewater utilities prepare,
respond, and recover from contamination threats and incidents.
WCIT is updated on an ongoing basis as new information or
contaminants warrant inclusion.

WCIT contains information on more than 800 contaminants. This information can
be accessed through toolbars, menus and a Google-like search function. Features of the database
include profiles, risk calculator, reports and other resources.


key topics, including: contaminant
names (including CAS and NCBI,
other names and related
contaminants); physical or pathogen
properties; availability; fate and
transport; medical information;
toxicity and infectivity; water quality
indicators; environmental indicators:
drinking water treatment; wastewater
treatment; laboratory methods and
field tests; infrastructure
decontamination; threat type; and
helpful response advice for utilities.

Contaminant information is presented
in either comprehensive, partial or lab
method PROFILES. Comprehensive
profiles include information in all
14 topic areas, while partial profiles
include information in some of the
topic areas. Lab method profiles
include analytical method information.

RISK CALCULATOR Provides an indication
of the relative risk which can be used as a
benchmark for broadly assessing the impact of
contaminants via a specified exposure route.

WCIT provides three different types of
REPORTS: Profile, Information Officer,
and User Selection. These are print-friendly
formatted content customized to your needs
that can facilitate collaboration in the field. For
example, the Information Officer Report
presents basic information on the
contaminant, that can be used as a reference
when developing briefings and
communicating with the public.

Provides RESOURCES that can supplement
the information contained in WCIT. The
resources cover thirteen topic areas with a
brief resource description and their respective
links to access them. For example you will
find the following topics: accessing laboratory
support, drinking water security, technical
assistance, and more.

WCIT Data Supports Multiple Users in the Water Sector


Comprehensive Profile, last updated on 02/14/2023 04:36 PM
~ Show References Comprehensive Profile Report

Information Officer Report


Risk Calculator
| User Selection Report

For EPA, other federal
organizations, and
technical assistance
providers, WCIT
provides information on
contaminant properties;
availability; fate and
transport; water quality
and environmental
indicators; and treatment
process options.

| | General Information Q	Fate and Transport	Q Water Quality Indicators

Q Contaminant Summary v Q	Medical Information	Q Environmental Indicators

~ Other Names/Forms Q Toxicity Information	~ Wastewater T reatment

| | Physical Properties | |	Laboratory Methods and Infrastructure Decontamination

~	Field Tests

| | Drinking Water Treatment

Contaminant Summary

For State Drinking
Water Programs, WCIT
provides information on
threat type; contaminant
properties; water quality
and environmental
indicators; analytical
methods; and toxicity.

For Utilities, WCIT
includes drinking water
and wastewater treatment
and infrastructure


Dicrotophos is an organophosphate pesticide that occurs as a yellow to brown liquid with a mild
ester odor (fruit or flower-like odor). Dicrotophos is used as an insecticide to control flea hoppers,
aphids, thrips, stink bugs and plantbugs in cotton. Dicrotophos can also be applied by tree
injection to control insects on ornamental and non-food bearing trees.

Threat Type:

Dicrotophos is a public health and environmental threat. It is highly toxic to humans through the
ingestion, inhalation, and dermal pathways of exposure. It isalso hazardous to animals.


Dicrotophos is manufactured in the U.S. Most uses are restricted. Acquisition of sufficient material
to effectively contaminate drinking water would not be difficult. Available formulations of
dicrotophos range from 0.5% to 90% active ingredient. Low background levels of dicrotophos
also have been known to occur in surface waters in the U.S.

Fate and Transport:

Dicrotophos is stable in water under normal conditions. It hasa half life of 72 days in water at pH
7 and 25C. For some organophosphate pesticides, the degradation by-products have higher
toxicity than the original pesticides themselves, asa result of the reaction between chlorine or
ozone and pesticides in raw water during water purification. Pesticides having the P = 0 bond in
their molecules are easily degraded by chlorination to produce oxons as primary degradation by-
products. Since oxons are stable against chlorine and hardly degradable, they may remain in
purified water from water purification plants if chlorinated organophosphate pesticides are
present in raw water. Dicrotophos is unlikely to volatilize or breakdown in sunlight. Dicrotophos
may adsorb to sediments and therefore may also be expected to adsorb to infrastructure. It is
also corrosive to some metals and is soluble in water. Based on its solubility, slow hydrolysis rate,
and lack of volatilization, dicrotophos would be expected to persist in dri nking water long enough
to be a public health threat.

Early Warning, Field Tests,
and Analytical Methods:

The pH, conductivity, and total organic carbon (TOC) of water are likely to increase if dicrotophos
is added, while chlorine levels may decrease. Dicrotophos has a mild ester odor in its pure form,
but it is unknown whether this odor would be detectable when diluted in drinking water. Field
tests are available to detect the presence of organophosphate pesticides, but no specific field
tests were found to detect dicrotophos. Several gas chromatography methods are available for
laboratory analysis of dicrotophos in water.


Dicrotophos is highly toxic with an oral median lethal dose (LD50) of 13 mg/kg. Dicrotophos
poisons humans and animals by inhibiting the enzyme acetyl cholinesterase, which is essential
for muscle contraction. Ingestion is the primary route of exposure, but exposure via the dermal
and inhalation pathways is also possible. Exposure may result in symptoms such as sweating,
headaches, difficulty breathing, blurred vision, and gastrointestinal distress. Symptoms observed
will depend on the route of exposure and dose, but mortality is possible at high doses. Symptoms
may appear between five minutes and 12 hours after exposure depending on thedose. An
antidote is available and is most effective within 15 minutes of a fatal dose. Full recovery may
take several weeks.

Drinking WaterTreatment:

Reverse Osmosis (RO) can be a highly effective treatment process for the removal of dicrotophos.

Utility Response

Any domestic use of contaminated water may present a public health threat due to the potential
for dicrotophos to cause acute health effects via all routes of exposure. Boiling would not remove
dicrotophos. Dicrotophos contaminated water should not be used to water livestock, as
dicrotophos is toxic to mammals. Flushing of water contaminated with dicrotophos from the
distribution system without any additional treatment could pose a threat to the environment due
to its toxicity to fish and other wildlife. Use of contaminated water for irrigation would not harm
crops, but exposure of people and animals to irrigation water should be avoided.


A highly effective procedure to decontaminate solid surfaces and equipment of the infrastructure
is washing surfaces with a sodium hydroxide solution followed by rinsing.


Direct photolysis is a highly effective treatment method for the removal of organophosphorous
pesticides (OPPs). Photodegradation of OPPs in UV/Fe2+/H202 systems nearly completes
degradation within 240 minutes.

This image is a
contaminant summary.

More information is
available by selecting
additional topics.

For Emergency
Responders, WCIT
provides support for
response efforts by
offering information on
toxicity; first aid and
medical treatments; fate
and transport; and field
detection and analysis.

For Environmental
Laboratories, WCIT
provides information
on analytical methods
for unregulated

For Public Health
Officials, WCIT provides
valuable contaminant
specific information
including clinical signs,
treatment, and toxicity
values based on routes
of exposure.

REGISTERING FOR WCIT IS EASY AND FREE To apply for access as a member of the Water
Sector, visit https://www.epa.gov/waterdata/water-contaminant-information-tool-registration.

For more information on WCIT, visit
https://www.epa.gov/waterdata/water-contaminant-information-tool-wcit or send an email to WCIT@epa.gov.

Office of Water (4608-T) | EPA817-F-23-006 | October 2023