Description
Paradichlorobenzene is a white solid in the halogenated organic class of chemicals. It has a sweet, mothball-like odor and evaporates easily. It is widely sold for household use as deodorizer and moth control blocks for toilet bowls, diaper pails and closets, and as mothballs. PDCB is also an ingredient in some toilet bowl cleaners, miticides for pet birds, rodent repellents, and insecticide used on fruit trees.
Children may be exposed to PDCB fumes, or they could accidentally ingest the moth balls.
Paradichlorobenzene is also used to manufacture plastics and other industrial chemicals.
Health Effects
Immediate Health Effects
- If SWALLOWED, 1,4-dichlorobenzene is Moderately Toxic
- If ABSORBED THROUGH SKIN, 1,4-dichlorobenzene is Low Toxicity
- If INHALED (SNIFFED OR BREATHED IN), 1,4-dichlorobenzene is Low Toxicity
Longterm or Delayed Health Effects
- This chemical is likely to cause cancer. It is considered a Probable Carcinogen by the the Department of Health and Human Services and the International Agency for Research on Cancer.
- Allergen
- Neurotoxin = Can harm brain and central nervous system development after birth.
Other
- High vapor concentrations may irritate eyes, nose, skin and respiratory tract. Other effects include headache, weakness, dizziness, loss of appetite, nausea, vomiting, trembling, numbness in the arms and legs and swelling of the eyes, hands, and feet.
- Prolonged skin contact may produce a burning sensation or allergic rash/dermatitis.
- Long-term exposure may damage the liver, kidneys, lungs, skin, and central nervous system, and may damage blood cells, causing anemia.
- Eating contaminated products for long periods can result in skin blotches and anemia.
- Cancer. Test animals exposed to PDCB developed kidney and liver tumors.
How Exposures Occur
From Indoor Air
- Children can be exposed to paradichlorobenzene by breathing contaminated indoor air. Indoor air levels of PDCB can rise due to use of mothballs, deodorizing blocks for toilets and diaper pails, some toilet bowl cleaners and pesticides that contain it. Clothing stored with mothballs may continue to emit paradichlorobenzene vapors, exposing children if they spend time in or near such clothing. Inhalation is the primary source of exposure.
Accidental Ingestion
- Children may eat mothballs or deodorizing blocks used in toilets and diaper pails, or swallow cleaners containing paradichlorobenzene. They can also ingest it by touching these products and putting their fingers in their mouths.
Drinking Water
- Children can be exposed to PDCB from drinking contaminated water. This chemical is regulated under the Safe Drinking Water Act.
In Foods
- Children may be exposed to PDCB through eating beef, pork, chicken, and eggs from animals kept in stalls where p-DCB was used to control odors, and through eating sportfish from contaminated waters.
- Children can also be exposed through the placenta and through breastfeeding
Significant Statistics
Paradichlorobenzene has been found in 13 percent of the drinking water samples from U.S. surface water sources.
Public Health Statement for 1,4-Dichlorobenzene. Agency for Toxic Substances and Disease Registry,. August 2006. http://www.atsdr.cdc.gov/toxprofiles/phs10.html
1,4-dichlorobenzene is not naturally occurring. The chemical is man-made.
Public Health Statement for 1,4-Dichlorobenzene. Agency for Toxic Substances and Disease Registry, August 2006. http://www.atsdr.cdc.gov/toxprofiles/phs10.html
Approximately 5 million pounds are marketed each year, mostly in moth ball form.
Reregistration Eligibility Decision for Para-dichlorobenzene. EPA. December 2008. http://www.epa.gov/oppsrrd1/REDs/para-dichlorobenzene-red-revised.pdf
Most of the chemical that enters your body leaves through the urine in less than a week. About 1-2% leaves through exhaled air or feces. A small amount may remain in your fat cells.
Public Health Statement for 1,4-Dichlorobenzene. Agency for Toxic Substances and Disease Registry, August 2006. http://www.atsdr.cdc.gov/toxprofiles/phs10.html
Solutions
How to detect 1,4-dichlorobenzene
- Read labels. Look for paradichlorobenzene in ingredient listings on packages of mothballs, deodorizing blocks, toilet bowl cleaners, mite sprays and other pesticides. White deodorizer blocks labeled as cedar, pine, lavender, or other natural scents may contain or consist primarily of paradichlorobenzene. If you are unsure about the ingredients in such products, ask the manufacturer to send you a Material Safety Data Sheet (MSDS), which they are required to provide.
Smell the product (carefully). Paradichlorobenzene smells similar to mothballs and is the sweet odor often encountered in public restrooms.
A search for paradichlorobenzene in the National Library of Medicine’s Household Products Database will show a list of brands that contain it.
- Paradichlorobenzene (1,4-dichlorobenzene, PDCB) is regulated under the Safe Drinking Water Act. This law requires that community water systems monitor PDCB levels, and make public when levels exceed the set Maximum Contamination Level (MCL). The MCL for PDCB has also been set at 75 parts per billion.
Community water systems are required to produce annual consumer confidence reports and mail them to every water customer.
If your water source is a well, your water is not monitored for contaminants as is required for public water supplies by the Safe Drinking Water Act. Private testing of the water is necessary.
Even if your water comes from a community water system, contaminant levels can vary from house to house. You can have your water tested by sending samples to a certified laboratory.
You can search for water quality reports from your water provider, obtain information on well water testing and find a list of state-certified drinking water laboratories at the U.S. EPA’s Office of Water’s website or call the EPA’s Safe Drinking Water Hotline, 800-426-4791.
How to minimize exposure to 1,4-dichlorobenzene
- Avoid using mothballs and deodorizer blocks in your home, particularly if you have small children,who may mistake them for candy and eat them. If you have used them, open windows and provide adequate ventilation throughout the home to reduce naphthalene fumes. Mothball-scented clothing and bedding should be thoroughly washed before use. Wash mothball-treated clothing and bedding thoroughly before use.
- Dispose of mothballs and deodorizing blocks carefully to prevent children from finding them. Contact you local sanitation department or look up the hazardous waste rules in your community on Earth 911.
- Avoid accumulating unused woolens. Never store dirty clothes.
Alternatives
- Use cedar or other herbal repellents: Store clean clothing in airtight containers or sealed bags with cedar blocks, cedar shavings (available as cage bedding in pet stores), or cedar oil. Place cedar in drawers and closets. Inspect any used clothing or furniture carefully for moths or larvae before bringing them into the house, or clean them first.
- To minimize unpleasant odors, keep toilets, garbage cans, and diaper pails clean. Leave an open box of baking soda nearby to absorb odors, and be sure your home is well-ventilated.
- Use mild and nontoxic cleaners. See Recipes for Safer Cleaners.
- Vigorously shaking clothes will remove larvae and eggs (remember to vacuum well afterwards). And the heat of the dryer will also kill larvae and eggs.
For More information
Books, articles, factsheets and reports
Goldberg, Jennie. Clothing Moths. Washington Toxics Coalition, September 1995.
1,4-dichlorobenze CAS No. 106-46-7: http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s062dich.pdf
Reregistration Eligibility Decision for Para-dichlorobenzene. EPA. December 2008.
http://www.epa.gov/oppsrrd1/REDs/para-dichlorobenzene-red-revised.pdf
Other government agencies
Agency for Toxic Substances and Disease Registry
Division of Toxicology
1600 Clifton Road NE, Mailstop E-29
Atlanta, GA 30333
800-447-1544
http://www.atsdr.cdc.gov
U.S. EPA Office of Ground Water and Drinking Water
Ariel Rios Building
1200 Pennsylvania Avenue NW
Washington DC 20460-0003
EPA Safe Drinking Water Hotline: 800/426-4791
http://www.epa.gov/safewater/
Nonprofit organizations
Other websites
Environmental Defense Chemical Scorecard
http://www.scorecard.org
Pesticide Action Network Pesticide Database
http://www.pesticideinfo.org
Pesticide Action Network Pesticide Advisor
http://www.panna.org/resources/advisor.dv.html