Cambridge will continue its efforts to establish a paraquat testing laboratory despite the opposition of the Massachusetts Public Health Department. The department will test for the presence of the herbicide in marijuana to determine whether the establishment of county or city testing centers is necessary, Lynn Knox, director of public relations of the Massachusetts Public Health Department, said yesterday.

Paraquat is a toxic herbicide sprayed on Mexican marijuana to halt its growth. The City Council approved a marijuana testing proposal on Monday which would grant power to the city health commissioner, university and other research facilities to test for marijuana contaminated by paraquat.

Because it is estimated that only 10 per cent of the marijuana in Massachusetts is from Mexico, the Massachusetts Public Health Department will test for paraquat in marijuana throughout Massachusetts to determine whether the existence of the chemical warrants a state-wide testing program, Knox said.

"If the tests reveal that a lot of the marijuana tested is contaminated by paraquat, we may encourage the establishment of either city or county testing laboratories," Knox said.

The department is encouraging Cambridge technicians and attorneys to hold off on paraquat tests until the state proves that the scale of the paraquat problem warrants city testing laboratories, Knox said.

Bushed

The Cambridge police will test for paraquat content in the marijuana it has confiscated from people in this area when it is granted permission by the District Attorney, Robert Healy, assistant city manager, said yesterday.

Although it is proven the effects of heavy paraquat ingestion are severe, the effects of low concentrations of the chemical are unknown, Dr. David Kinlock, deputy commissioner of public health, said yesterday. "As it looks now," Kinlock added, "most marijuana users will not be exposed to heavy doses of paraquat."