Solvents Poured Down the Household Drain May Cause Pollution

While household chemical products are generally safe for the uses they are designed for, some may become harmful to the environment as they accumulate in non-target areas. For this reason you should not put these products down a drain.

When you pour hazardous household products down the sink or flush them down the toilet the hazardous materials enter either a septic system or a municipal sewer system. If you have a septic system, wastewater from your house goes into a tank buried underground. The solids settle out and partially decompose. The remaining wastewater then goes into a drain field where the natural processes ongoing in the soil help to further break down the wastewater. Toxic materials in that wastewater can kill the helpful bacteria and the system will not operate properly. Some toxic materials move through the soil untreated or unchanged. When this happens ground water or surface waters may become contaminated. For example, many paint removers and aerosol paint products contain the chemical methylene chloride which does not dissolve easily in water.

This chemical can pass directly through a septic system without breaking down at all. Chlorine bleach can also pass through a septic system without breaking down. Also the chlorine can react with organic matter to form new toxic chemicals. If your home is hooked to a municipal sewage system, your wastewater is piped to a central sewage plant. After treatment, it is discharged into area like rivers, lakes and streams. Most municipal systems rely on bacteria or other organisms to decompose the waste. Some hazardous household waste can pass through the system unchanged and thus pollute the water downstream. In addition, hazardous household wastes poured down the drain may corrode the plumbing or collect in the trap and release fumes through the drains.

Most sewage treatment facilities are not capable of removing such toxic substances. You should also be aware that in most cases, anything put into the storm sewer system goes directly to the receiving lake or river completely untreated. So, before you dump anything down a drain or into a storm sewer, remember that you or others may be drinking it somedays. For those substances that you have at home now and want to get rid of, such as old paint, find out whether there is a hazardous waste disposal site in your community and take them there. Contact your local environmental officials or extension office for assistance. Make sure the containers are labeled to indicate the contents.

Some hazardous household wastes can be flushed down the drain as long as they are followed by plenty of water. This recommendation applies if a hazardous household waste will be neutralized by water or if the municipal or sanitary sewage system is able to remove the toxins or render them harmless.