Oryzalin is an herbicide used to control broad-leafed weeds and grasses. It's used to prohibit seed growth primarily around fruit and nut trees, vineyards and ornamental plants.
It breaks down slowly in water and can be mobile in some soils, making it a potential groundwater concern.
According to the Extension Toxicology Network, oryzalin is “practically nontoxic by ingestion,” causing only minor irritation to they eyes and skin. Laboratory animal tests have shown that long term exposure to oryzalin can cause changes in blood, liver and kidneys, and it is classified by the EPA as a possible human carcinogen.
According to the EPA, oryzalin can be effectively treated with activated carbon.
Sources: EPA (1), EPA (2), EXTOXNET, WSDOT, Photo: WikiMedia, author: Amanda Slater
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