Just because your home, or a home you’re considering buying isn’t near a toxic waste site doesn’t mean soil is free of contaminants. Contamination by heavy metals, particulates from automobile exhaust, pesticides, and petroleum products can occur in ordinary home settings. Homes built on former farmlands or former military sites can have hidden toxins in soil. Soil testing can be done to determine whether contamination is present, which is important if you have young children or if you plan to do gardening or major landscaping.
Soil chemistry isn’t static, but changes over time. Chemical and biological process combine some soil materials and break others down. Soil also changes when plants grow from it, or when it is disturbed by animals. When particulate airborne pollutants blow in and settle on the ground, some of those particulates may work their way into the soil. Since soil changes constantly, soil testing should be done quickly after a soil sample is extracted for testing. Some soil samples are frozen or air dried for preservation if testing cannot be done within a short time period.
Soil contaminants may be liquid or solid, and they may lodge into spaces between soil particles, or they may chemically or mechanically bond with soil particles. Contamination can affect the quality of plant growth significantly, since plants can absorb pollutants through their root systems. Contaminated soil may be harmful to children, who are prone to picking things up off the ground and digging in the dirt around their homes. Home vegetable gardens may be affected by soil contamination too. Many home gardeners request soil testing both to learn of possible contaminants and to learn about soil nutrients.
Some toxic chemicals occur naturally in soil. For example, some metals and elements like arsenic are often found in soil that has not been contaminated. Human activity is a major factor in soil contamination. For example, pesticide and herbicide residue can build up in farmlands over the years. Spills of products like motor oil and solvents can contaminate soil, and underground tanks can leak. Buried toxic waste can leach into soil and find its way into groundwater and then farther along to nearby areas of soil. Lead may be found in soil near heavy traffic area or around homes built before 1978.
Sometimes housing developments are built on former farmland on which pesticides and herbicides may have been used for many years. Developments may also be built atop former military properties where the soil was contaminated by military activities. There have been developments in some places where gardening isn’t permitted due to contamination of soils. Most housing developments don’t deal with this level of soil contamination, however. Some home inspectors are licensed to perform soil testing, and many potential home buyers choose to have soil testing done, particularly if they plan on gardening for food or if they have small children who will be playing outside for long periods.
MD Mold Testing is licensed to perform soil testing and serves residents and home buyers in Montgomery County, Washington DC, Delaware, and northern Virginia.