Paraquat, like other crop protection active ingredients, is regularly reviewed by national and global regulatory authorities and studied by independent researchers.
Recent Regulatory Decisions
In recent years, paraquat has been approved for re-registration following rigorous evaluation by several regulatory authorities. Paraquat has also received periodic re-evaluations of both toxicology and dietary residues by the WHO and FAO, respectively.
Examples of recent comprehensive toxicology reviews include Australia (2016), US EPA (2019) and Japan (2022). Recent re-registration decisions are from New Zealand EPA (December 2019) and the US EPA (August 2021).
The Australian Pesticides and Veterinary Medicines Authority (APVMA) have recently (October 2016) concluded and published a comprehensive review of the toxicology of paraquat under the Chemical Review Program:
“After consideration of the toxicological data submitted for the purpose of this review, the ongoing approval of this active constituent is supported. This review confirmed the existing health standards.”
In 2022 The Food Safety Commission of Japan (FSCJ) published (Food Saf (Tokyo) 10(4): 140-147) their risk assessment for paraquat. The effects on the lung were considered to be the most critical endpoints in their toxicology assessment. Paraquat was concluded not to be carcinogenic and not to have effects on fertility, teratogenicity, genotoxicity or immunotoxicity. The FSCJ concluded no obvious neurotoxicity concern relating to paraquat residues in foods potentially resulting in human dietary exposure when paraquat is applied according to the registered uses.
- In August 2021, the US Environmental Protection Agency concluded their periodic re-registration review of paraquat, details are summarized by the US EPA on their website: https://www.epa.gov/ingredients-used-pesticide-products/paraquat-dichloride
NGOs (Non-governmental organizatons) now routinely challenge US EPA re-registration decisions through the US Courts. As a result of an NGO lawsuit the US EPA will again review certain aspects of the paraquat 2021 re-registration decision with a mandate to complete the process in early 2025. On 11th July 2007 the Court of First Instance of the European Community (CFI) (now the EU General Court) issued a judgment annulling Commission Directive (2003/112/EC of 1st December 2003) which included paraquat in Annex I to Council Directive 91/414/EEC.
The CFI decision to annul the Annex I inclusion of paraquat criticised the way in which the re-registration procedure was handled and the manner in which the Commission interpreted the relevant laws and applied them to its analysis of the data. The CFI was not empowered to decide itself on the safety of the substance.
The CFI decision is not in itself a ban on paraquat, but as a result of both the decision and the expiry of measures permitting individual Member State authorisations to remain in force during the previous review of paraquat for inclusion in Annex I, the Member States had to withdraw or suspend their national authorisations.
In December 2003, the EU concluded “It has appeared from the various examinations made that there are uses of plant protection products containing paraquat which may be expected to satisfy, in general, the requirements laid down in Article 5(1)(a) and (b) of Directive 91/414/EEC, provided appropriate risk-mitigation measures and restrictions are applied.”
This statement, and the references therein, means that the EU scientific review concluded that there are uses of paraquat, following good agricultural practice, which will not have any harmful effects on human or animal health or on groundwater, or have any unacceptable influence on the environment. This decision allowed for continued registration of paraquat products in EU countries. The decision was subject to compliance with various requirements, including a stewardship program for operator safety and a monitoring program for operator health and wildlife incidents.
The EU review report and EU regulatory decision are available here
- In 2003, paraquat was reviewed under a periodic re-evaluation of toxicology under the Joint FAO/WHO Meeting on Pesticide Residues (JMPR). Its toxicological properties were evaluated and the acceptable daily intake (ADI) of paraquat was established. This allows an assessment of consumer safety to be made.
The 2003 JMPR report is available here
- In 2004, paraquat was reviewed under a periodic re-evaluation of dietary residues under the Joint FAO/WHO Meeting on Pesticide Residues (JMPR), “The Meeting concluded that the intake of residues of paraquat resulting from uses considered by the current JMPR was unlikely to present a public health concern.”
The 2004 JMPR report is available here.
The Codex Maximum Residue Limits for paraquat can be found here.
Global Registration Status of Paraquat
Paraquat is registered and sold in many countries around the world, including major agricultural markets with some of the most demanding regulatory systems, including: USA, Australia, Japan and New Zealand.