The Environmental Protection Authority has strengthened the rules governing the use of chlorthal-dimethyl, also known as DCPA, because of concerns about its effects on fetal development.
The new rules come after the EPA’s red alert on August 22 urging people to stop using weedkillers that contain this chemical.
This followed the United States’ Environmental Protection Agency banning the substance earlier in August.
US data found the substance can affect fetal development and cause low birth weight and irreversible, life-long impacts, such as impaired brain development and motor skills.
The EPA has introduced restrictions to New Zealand so the weedkiller can only be used on soil where specific crops are grown. Pregnant individuals or individuals who may be pregnant are prevented from using the substance or entering a site where it’s been used, and wide buffer zones further protect the public from spray.
All restrictions on the use of products containing chlorthal-dimethyl took effect from September 13.
“Putting these restrictions in place now is the quickest and most effective way for us to protect people’s health and safety,” Dr Shaun Presow, Hazardous Substances Reassessments Manager, said.
“We have consulted with organisations that use this herbicide, and we have found that it’s not widely used in New Zealand, especially compared with the United States.
In New Zealand, chlorthal-dimethyl is used mainly for controlling a specific weed in onion, garlic and shallot crops before the vegetables emerge from the soil.
“These crops aren’t sprayed directly, and the substance breaks down before harvest, so we can assure people there is no risk through exposure from vegetables,” Presow said.
The EPA’s next steps are to gather and analyse all information on how these weedkillers are used in New Zealand, before carrying out a full review that may lead to further restrictions or a ban.
The three products containing chlorthal-dimethyl that are registered for use in New Zealand are Dacthal, Deramot Xtra and Chlor-Back 75WG.
Read more about the new restrictions on chlorthal-dimethyl.
