A report on the recent poisoning of hundreds of Barrick Gold employees recommends the Dominican government amend its contract with the Canadian miner to ensure the country's interests are protected.

The Dominican Republic's Academy of Sciences and the Autonomous University of Santo Domingo said the contract between the government and the mining company contains clauses that limit national sovereignty in the case of disasters or health emergencies and therefore are not consistent with the Dominican state's constitutional obligations.

They also questioned the company's claims that the workers were victims of bacterial poisoning, noting that both the symptoms and the treatment they have received belie that conclusion.

"The symptoms and treatment correspond to chemical contamination," the study said, adding that the affected workers emitted a "penetrating and nauseating" odor.

According to the study, released Thursday, the victims's symptoms included teary eyes, stinging pain in the eyes and nose, itching in the upper extremities, headaches, nausea, dizziness, weakness, abdominal pain, diarrhea, decrease in muscular strength and signs of dehydration.

The report criticized the lack of communication surrounding the poisoning of more than 300 Barrick Gold employees at the Pueblo Viejo gold mine in the central Dominican town of Cotui.

It also denounced a "lack of transparency" in Barrick Gold's operations and noted that the affected workers are not enrolled in the Dominican health system, as is required by law.

Barrick Gold's presence in the country has been harshly criticized by environmental, civil society and community groups, which allege that the company's 25-year lease agreement, approved by Congress, is economically detrimental to the country.

Dominican officials, however, say the conditions in the lease deal are fair and that the agreement will be beneficial to the nation.

The controversy intensified after Congress revised the original contract to include a clause allowing Barrick to defer payment of moneys owed to the government until the operation achieves a profit margin exceeding 10 percent.