Propanil is an herbicide used to control broad-leaf and grassy weeds, primarily in rice crops. It degrades quickly in water, transforming into several different metabolite compounds, two of which—3,4-dichloroaniline and TCAB—are considered to be of greater health concern than propanil itself.
Propanil is considered to be of low toxicity, though the World Health Organization warns of several toxic symptoms:
Exposure produces local irritation and central nervous system depression. Ingestion causes local irritation with a burning sensation in the mouth, oesophagus and stomach, gagging, coughing, nausea and vomiting, followed by headache, dizziness, drowsiness and confusion.
Animal studies of long term exposure have shown adverse effects on the spleen and liver, and reductions in body weight. It is not believed to be carcinogenic.
The EPA recommends activated carbon for the treatment of propanil.
Sources: WHO, EPA, EPA (2), EXTOXNET, Photo: geograph.org.uk, author: Walter Baxter
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