Green Party leader Mr Trevor Sargent has accused the Government of "sacrificing human and animal health" by failing to address the high incidence of disease in west Limerick.
Mr Sargent was reacting to a report yesterday that human cancer rates in the Cappagh/Askeaton area of Co Limerick had almost doubled in two years.
The report, from the Cappagh Farmers Support Group, also highlighted the failure of the Environmental Protection Agency (EPA) to discover the cause of death of hundreds of cows and horses in west Limerick.
"It is clearly unnatural what is happening in this area.
"Newborn calves are dying after the umbilical cord is cut. Cattle are dying of mastitis even though there is not a trace of the disease during milking," Mr Sargent said.
He also noted the high incidence of human health problems, particularly in children.
Deputy Mary Upton, Labour Party spokesperson on Agriculture, said the farming community deserve some explanation for the ongoing high level of cattle fatalities.
She said for many farm families in the area, "the financial and emotional toll caused by these cases is immense" and said the Department of Agriculture must re-examine the situation and consider a new inquiry.
