Soil amendments - heavy metal data

Soil Amendment Heavy Metal Data Analysis

The data shown in the documents below is from a database owned and managed by the Washington State Department of Agriculture. It includes heavy metal data analyses for the commercial products sold in Washington State. The manufacturers provide the data.

We analyzed the data by dividing and color coding the results into three groups:

green - soil amendments with metal (arsenic, lead or cadmium) concentration at or below US average soil backgroundⁱ;
yellow - metal above soil background and at or below Washington State clean up standardsⁱⁱ
pink - soil amendments with the metal concentration above the Washington State clean up standardsⁱⁱ

Metal Concentrations, ppm

Arsenic Cadmium Lead

Background
4

0.25

10

Clean up Standard
20

2

250

Some of the data was expressed as being below a detection limit. In that case, we assumed that the concentration was the detection limit. Different manufacturers’ analyses had different limits of detection, and some of the limits of detection were higher than the background. In this case, the product was coded as being more contaminated than is actually the case.

Fertilizer Lists

Fertilizers available on Vashon

All fertilizers in the WSDA database sorted by Product Name / by Manufacturer

ⁱATSDR Fact sheets for Arsenic, Lead and Cadmium http://www.atsdr.cdc.gov/toxfaq.html
ⁱⁱhttp://www.leg.wa.gov/RCW/index.cfm?fuseaction=chapterdigest&chapter=70.105D

This webpage supports the Heavy Metals Remediation Committee of the Vashon-Maury Island Community Council
It is funded in part by Island Remediation and Public Participation Center through a grant from the Washington State Department of Ecology