Weed killer is sprayed in an urban area of Naxxar in this photo provided by the Malta Organic and Agriculture Movement.

The use of herbicides in urban areas by contractors engaged by local councils could be a factor behind the high level of weed killer in our bodies, according to the Malta Organic and Agriculture Movement.

Urine samples in nine out of 10 people in Malta tested positive for the weed killer glyphosate in a Friends of the Earth study published earlier this month.

Malta had the highest rate of positive tests out of all 18 countries that took part in the study.

All of the volunteers who provided samples lived in urban areas and none had handled or used glyphosate products in the run-up to the tests.

A MOAM spokesman said: “Over recent years we have been battling with various authorities over the use of herbicides instead of mechanical means to control weeds in built-up areas, but have always met resistance.”

Naxxar council, one of the authorities mentioned by the MOAM, said it does not interfere in the methods its contractor uses to eliminate weeds in urban areas, provided they are in accordance with the law.

The council has not met since the report was published but executive secretary Paul Gatt said it intended to discuss the use of herbicides at a future meeting.

The MOAM does have at least one ally on local councils in the form of St Paul’s Bay mayor Mario Salerno, who was elected in March.

Even before the report was published, Mr Salerno said contractors in his village had been instructed to use grass cutters instead of herbicides to eradicate weeds, which had built up resistance to synthetic chemicals.

“Since taking over, I have given instructions that the principle of ecology should be a top priority in our locality. Grass cutting is the best practice for eradicating weeds. It is more costly, but in the end, herbicides bear hidden costs,” he said.

Glyphosate was first marketed by Monsanto under the name Roundup in the 1970s. Numerous companies now produce it under different trade names.

Environmental groups are concerned that the effects of glyphosate on health are not fully understood and the process of determining safe levels for humans is susceptible to industry lobbying.