Green Party MPs say workers who cleaned up the nation's most contaminated site, near Nelson, should be given the same access to state care as others exposed to dangerous chemicals.
A leaked Department of Labour report into a clean-up at the Fruitgrowers Chemical Company site in Mapua several years ago found significant failures by the Ministry for the Environment and the company responsible for the clean-up, EDL.
It says medical assessments of four workers show a variety of problems such as collapsing, headaches, nausea, visual disturbances, fatigue and slurred speech, and it does not rule out the possibility other workers could suffer future work-related health problems.
A Green MP Catherine Delahunty says the report should be recommending the workers get the same access to medical checks and treatment as those exposed to dioxin at the old Whakatane sawmill.
In 2010 the Ministry of Health offered surviving employees of that mill free health checks and support.
Ministry for the Environment officials say they are offering medical assessments to all workers involved in the Mapua clean-up, as recommended in the report.
The ministry says it has contacted the firms involved asking them to offer a medical assessment to the 30 or so people who worked at the site.
Decontamination began in 1999 at the former Fruitgrowers Chemical Company site, where chemicals had leached into the ground, but the report said not all possible safety precautions were taken during the soil remediation.
The report now recommends the Department of Labour upgrade its guidelines on cleaning up contaminated sites to include that, in such projects, workers are encouraged to report any poor health symptoms.
A man involved in the clean-up, who was not part of the report, said standards were lacking and in one particularly bad area workers wore no protective gear.
This man, who does not want to be named, said he was fired for speaking out about the way the clean-up was operated.
And a woman who lives opposite the Mapua clean-up site says the company responsible for cleaning it up should be held to account for poor safety standards.
Annette Walker, whose property borders the site, says it was difficult to get EDL to listen to complaints about the clean-up and she never received the results of tests done on her property.
The Department of Labour is not commenting on the claims or the report until it is officially released next week.
But in a brief statement, the department said it has already acted on several of the report's recommendations and how to improve the clean-up of contaminated sites in the future.