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Greenpeace says it is unbelievable that New Zealand continues to use a herbicide now banned in Australia and the United States.

In August, the United States took the unprecedented step of banning Dacthal herbicides, or DCPA, used to control weeds in vegetable crops, citing possible irreversible harm to unborn children.

It was the first time in forty years that the U.S. EPA urgently stopped the use of chemicals because of the potential harm they can cause to a developing fetus.

Australia now follows the United States in completely banning the use of products containing dimethyl chlorthal.

Following the US ban, the New Zealand Environmental Protection Authority reviewed the use of dacthal and introduced stricter rules regarding its application, but dropped the ban.

However, on Tuesday its head of hazardous substances reassessments told RNZ it was reviewing the decision but it could not be rushed due to legal requirements.

Greenpeace executive director Russell Norman said the EPA should immediately stop using it.

“It’s outrageous that the New Zealand EPA is allowing the use of these chemicals. When you look at the conditions they apparently place on the use of these chemicals, you’re sort of supposed to know if you can or not be pregnant if you’re a farmworker, and then you have to somehow avoid going to a farm that in the previous five days may have used these chemicals.

“I just think it’s completely irresponsible to put farmworkers in this position where they have to make decisions about a chemical that everyone is banning,” he said.

Norman said he would write to the EPA to ban the use of dacthal here, but he doubts he will succeed.

Chlorthal dimethyl is not widely used in New Zealand and Norman said for this reason a ban would have little effect and should be easy to implement.

He said that in the United States, DCPA is widely used and banning its use would have significant impacts for vegetable growers, but the United States EPA nevertheless decided to ban it.

The Environmental Protection Authority has said it could follow the United States and Australia in banning the use of DCPA herbicides in New Zealand – but it could be a year before that ban comes into force.

Rethinking the ban is possible – EPA

Shaun Presow, head of hazardous substances reevaluation at the EPA, said new rules had been imposed on the use of the herbicide following the US ban.

The EPA believed the rules protected people’s health, but it was re-evaluating the chemical’s use.

The process could not be rushed due to legal requirements.

“There are hurdles we have to jump through. It takes time. We have to submit a request for re-evaluation before we can possibly suspend approvals,” he said.

A ban was possible, but in the meantime the EPA believed the rules imposed in September protected public health.

DCPA weed killers can only be used on onions, garlic and shallots before they emerge, and only once per calendar year.

Users should maintain broad buffer zones to better protect the public.

Presow said these crops were not sprayed directly and the substance broke down before harvest, so “we can assure people there is no risk from exposure to the vegetables “.

In New Zealand there are two products containing the herbicide approved for use by the MPI: Dacthal and Chlor-Back 75 WG.

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