There is a consensus among the leading regulatory authorities globally that paraquat must be used with care because formulations of paraquat are irritant to eyes and skin. However, provided that basic good agricultural practices are observed, paraquat can be used without significant health risk.
- In their Health and Safety Guide No. 51, the International Program on Chemical Safety (a collaborative program of the United Nations Environment program, the International Labor Organization, and the World Health Organization (WHO)) concluded that “with reasonable work practices, including safety precautions, hygiene measures, and proper supervision, occupational exposure during the manufacture, formulation and use of paraquat will not cause a hazard. However, the undiluted concentrate must be handled with great care, because improper work practices may result in the contamination of the eyes and skin”
- In the European Union (EU), the opinion of the independent expert body the Scientific Committee for Plants (SCP) was that “the results of the field studies conducted in various countries indicate that the exposure models markedly overestimate the actual exposure to paraquat in real working situations. Thus modelled exposures cannot be used as the only basis for operator risk assessment. Based on the field exposure studies, corroborated by information on health surveys on operators, the SCP is of the opinion that when paraquat is used as a plant protection product as recommended under prescribed good working practices, its use does not pose any significant health risk for the operators.” (SCP, 2002).
- In their review report for paraquat, the European Commission (EC) required that Member States pay particular attention to the protection of operators, in particular for knapsack and handheld users. “The availability of the product should be limited to bona fide agriculturalists, horticulturalists and professional users” and “the maximum spray concentration must not exceed 2g bipyridyl/litre for knapsack and hand held applications” (EC, 2003)
In their RED facts document, the US Environmental Protection Agency (EPA) required that post-application, re-entry workers observe:
“a 12-hour Restricted Entry Interval for the uses of paraquat for pre-emergent or early-season weed control and weed control for orchards and vegetable crops”
“a 24-hour Restricted Entry Interval is required for desiccation and harvest aid applications of paraquat”.