Pacific Northwest Inspections Group offers complete soil testing services. Testing soil for levels of Cadmium,lead and arsenic. Most important for playgrounds at schools and daycares, these contaminates have already been found throughout both King and Pierce County.

   If a playground is contaminated, measures to clean up or make the area safe include simple solutions such as fencing, re-sodding or laying down woodchips at the area.

Soil Inspection

   Arsenic is leaking out of huge wooden playgrounds that volunteers built all over the State of Washington. It's leaking beneath decks and state park boardwalks, at levels that are dozens of times -- even hundreds of times -- higher than the state considers safe. And discarded pressure-treated lumber is leaking arsenic out of unlined landfills, state experts say, posing a threat to drinking water.

What is Known about Health Risks from Exposure to Low-to-Moderate Levels of Arsenic and Lead in Soil?

The risk of developing health problems from arsenic or lead depends on the amount of exposure and the concentrations to which a person is exposed.  The greater the exposure or the greater the concentrations, the greater the risk.  Most information about the health effects of arsenic and lead comes from studies where exposures were greater than those expected from living and working in places with low-to-moderate levels of arsenic and lead in soil.  Health monitoring and research studies have not been carried out to the extent necessary to understand and document whether exposure to low-to-moderate level arsenic and lead in soil is causing or contributing to long-term health problems in Washington.   

Evaluating health effects at lower levels of exposure is difficult, and it is unlikely that conclusive scientific information to determine the health risks from exposure to area-wide soil contamination will be available in the foreseeable future.  In light of this uncertainty, there is disagreement among scientists about how the information that is available should be interpreted and used to assess the risks of exposure to low to moderate level soil contamination.  Some members of the scientific community argue that federal and state efforts to address low to moderate level soil contamination are not scientifically justified because there is no information demonstrating that health problems are being caused by exposure to such contamination.  Other members of the scientific community argue that arsenic and lead in soil have the potential to cause health problems at low levels of exposure—especially for people who are particularly sensitive to the effects of these contaminants.  In recent years, the majority of scientific review committees formed to evaluate the available scientific information on arsenic and lead have concluded that there is a sufficient scientific basis to justify efforts to reduce exposure to these contaminants.

What are Health Risks from Exposure to High Levels of Arsenic and Lead?

Exposure to high levels of arsenic and lead can cause health problems in people.  Arsenic can cause more than 30 distinct health effects, including nervous system damage, increased blood pressure, heart attack, stroke, and cancer of the bladder, lung, skin, and other organs.  Lead can affect many parts of the body, causing health effects that include increased blood pressure, kidney damage, and brain damage.  Although both children and adults can be adversely affected by lead poisoning, it is a particular concern for young children.  Arsenic and lead are both considered persistent contaminants.  This means that they bind strongly to soil and usually remain in the environment without breaking down or losing their toxicity, and thus can be a source of exposure for many decades. 

Where and how we sample depends on what question you want to answer.

Children are the most sensitive population for heavy metal contamination, because they often play in the dirt, they often eat dirt (about 10 percent of children actually eat dirt by the handful), their stomachs are more acid than adults’ (thus absorbing more heavy metal, proportionately), and their growing bodies and nervous systems are more sensitive to metals. If you have small children, you should sample in the areas in which they play.

We gather a small, approximately equivalent amount of dirt from 4 to 8 spots, sampling only the top two inches of soil in the lab. This is called a composite sample. 

Clean your sampling equipment by scrubbing with detergent, and rinsing at least three times in clean water. Repeat the sampling process in other child play areas.

Gardens are a concern because we are often eating the produce from them. However, be aware that different gardening methods can lead to greater or lesser uptake by plants. Furthermore, different vegetables take up different metals differently. Arsenic appears to be mostly in roots and stems, and less in leaves and fruits, while cadmium appears to be mostly concentrated in leaves. There is no hard and fast connection between the heavy metals in garden soil and the heavy metals in vegetables.

Gardens can be sampled in much the same way as child use areas, but we sample the first six to 8 inches of the soil (the root zone) instead of the top two inches.

Be aware that metal contamination varies a great deal over small distances. You may have one garden that is very bad while others are very good. Mixing them together may conceal the bad garden.

Property/Real estate assessments are asking whether the property as a whole is contaminated. To determine this, we take a random sampling over the entire property of at least ten separate, non-composited samples. They will give you a statistical assessment of the property.

Ask Yourself:

   Is the property within an area affected by historical smelter emissions?Parts of King, Pierce, Snohomish, and Stevens counties have a high probability of having elevated levels of arsenic and lead in soil based on historical emissions of metal smelterslocated in Tacoma, Harbor Island, Everett, Northport, and Trail, B.C. See associated smelter plume maps to determine which parts of these counties are affected or potentially affected by historical smelter emissions based on information currently available.

   Were apple and/or pear trees grown on the property before 1947?Lead arsenate was used as a pesticide to control the codling moth from about 1905 to 1947 in Washington State. It was used most heavily on apple and pear trees, but was also applied to other tree fruit crops in smaller quantities. Properties that had apple or pear trees on them during the period when lead arsenate was used (i.e., before 1947) have a high probability ofhaving elevated levels of arsenic and lead in soil, while properties that did not contain apple or pear trees have a low probability. Local planning and zoning departments, former property owners, and/or long-time residents of an area may have information about whether a particular property used to be an apple or pear orchard in the early to mid-1900s. The flowchart continues with additional questions if it is unclear whether apple or pear trees were grown on a property during the period when lead arsenate was used.

   Is the property in a historical apple or pear growing area?Properties within historical apple or pear growing areas in the state—including but not limited to the Yakima valley, the Wenatchee valley, areas near Lake Chelan, areas in Okanogan and Spokane Counties, areas along the Columbia River, and in small commercial or “backyard” orchards in western Washington—are more likely to have contained apple and/or pear trees during the timewhen lead arsenate was used. If the property is not within a historical apple or pear growing area, the probability that it has elevated levels of arsenic and lead in soil from lead arsenate pesticide use is low. As with the first flowchart question, local planning and zoning departments, former property owners, and/or long-time residents of an area may have information about whether a particular property is within a historical apple or pear growing region.

   Is the property on state or federal land?State and federal land is not likely to have been cultivated with apple or pear trees historically and therefore properties onstate or federal land are less likely to be contaminated from lead arsenate pesticide use than are other properties.

   Has property never been disturbed or was it developed from undisturbed land after 1947? Properties that have never been disturbed or that were developed from undisturbed land after 1947 would not have been cultivated with tree fruit crops duringthe time that lead arsenate pesticide was used, and therefore these properties have a low probability of having elevated levelsof lead and arsenic in soil from historical use of lead arsenate. Former property owners, developers, and local officials may haveinformation about the development history of properties.

   Is property above 2,500 feet in elevation (or above 2,000 feet if in Yakima County)?Apple and pear trees tend to be grown in river valleys and other lower elevation areas in Washington. If a property is at a relatively high elevation, it is less likely tohave had apple and pear trees grown on it during the early to mid 1900s, when lead arsenate was used as a pesticide, and therefore there is a low probability that elevated levels of arsenic and lead are present from historical lead arsenate use.

   Does the property receive less than 15 inches of precipitation annually? This question is designed to separate the areas of the state that generally need irrigated water to grow apple and pear trees productively from those that do not. Information about average annual rainfall may be obtained from the National Weather Service. •In general, areas receiving more than 15 inches of precipitationannually, such as in much of western Washington, would not haveneeded to rely on irrigation to grow apple and pear trees; the flow chart ends for these properties with a determination of unknown probability of lead and arsenic contamination from lead arsenate use. •Areas in Washington that receive less than 15 inches of precipitation annually, however, would generally need irrigation to cultivate apple and pear trees productively; these areas are most often in eastern Washington. Information on current and historical irrigation practices, therefore, could help determine the likelihood of lead arsenate pesticide contamination. The flow chart continues for these properties with the following twoadditional questions about irrigation.

   Is the property in an area where irrigation is routinely practiced?If the property is not located within a general area where irrigation has been routinely practiced, it is not likely to have been irrigated in the past. Since irrigation would have been necessary to grow apple or pear trees on the property because of its low annual precipitation, this implies that there is a low probability that elevated levels of arsenic and lead are present due to lead arsenate use. If, however, the property is in an irrigation area, the flow chart continues with the following question:

   Is the property in an area served by irrigation water prior to 1947?If the property is in an area where irrigation is routinely practiced currently, information on whether the property was servedby irrigation water before 1947, when lead arsenate pesticide use ended, can help determine whether there is high or low probability for arsenic and lead soil contamination from this source. Information on whether a property had been served by irrigated water historically may potentially be obtained by contacting local irrigation districts; County or City governments may also havemaps or other historical references with this information. •If the property definitely was not served by irrigated water prior to 1947 yet (from question 6) is in an area needing irrigation to cultivate apple and pear trees, it is unlikely that apple and pear trees were grown on the property and therefore there is a low probability that there is lead arsenate contamination present. •If the property, however, was definitely irrigated in this period and (from question 2) is in a historical apple or pear growingarea, there is a high probability that lead arsenate contamination is present.

Inspection Cost

Average turnaround time: 2 weeks
Fee for 3 day turnaround: call
Cost per sample (three metals): $175