There’s nitrate in your water

RESIDENTS of Benguet and Bulacan beware: your drinking water may be contaminated with nitrates.

Close to 30 percent of groundwater wells from these locations showed nitrates levels above the World Heath Organization (WHO) safety limit of 50 mg l-1 of nitrate (NO₃), according to an 18-page Greenpeace report on nitrates in drinking water in the Philippines and Thailand.

Contamination from nitrates is most likely in agricultural areas such as Benguet and Bulacan, where nitrogen fertilizers are used. Five out of the 18 artesian wells in Benguet and Bulacan contained nitrate levels well above the WHO drinking water safety limit. The highest levels were found in groundwater in Buguias, Benguet at 50 percent above the WHO safety limit.

Although one sample from Angat, Bulacan showed a high nitrate level, Greenpeace said that the highest nitrate level was found in Buguias based on the cumulative data set in that location.

Drinking water contaminated with nitrates can cause serious health problems, especially in children, according to the report. The greatest risk of nitrate poisoning is “blue baby syndrome” or methemoglobinemia, which occurs in infants given nitrate-laden water, and particularly affects babies under four months of age. Blue-baby syndrome can provoke cyanosis, headache, stupor, fatigue, tachycardia, coma, convulsions, asphyxia and ultimately death.

Nitrate-contaminated drinking water may also cause the development of cancers of the digestive tract. It has also been linked to other types of cancer such as non-Hodgkin’s lymphoma, bladder and ovarian cancers.

“The nitrates pollution that we discovered in farming areas is particularly worrisome — communities think that the water they drink everyday is clean because physically, it doesn’t smell bad or look bad. But it is actually laced with nitrates from fertilizers which people don’t normally associate with pollution,” said Greenpeace Campaigner Daniel Ocampo in a press release.

The study sampled water from four groundwater and surface water sources in Benguet and Bulacan.

While Greenpeace says that the use of nitrogen fertilizer in the Philippines and Thailand is “relatively low” compared to industrialized countries, the excess use of these fertilizers is one of the main sources of the nitrogen pollution of water bodies. “When farmers apply fertilizer to farms, half (or more) of that fertilizer generally does not stay on the soil to help crops grow, but rather is carried away in water and air. The run-off of fertilizers in water first reaches local wells and creeks, from where it travels to rivers and lakes and ultimately the coast,” the report said.

The report indicates that the nitrates pollution in drinking water sources sampled in the Greenpeace study correlates with intensive farming practices which use excess nitrogen fertilizers. Farmers may apply excess fertilizer due to a a perception that it is always better to apply in excess to secure a good harvest, or a lack of expertise about specific crop requirements and efficiency in the timing of application. But the report also says, “Throughout developing countries it is common to find that agrochemical dealers [in local shops] are in reality acting as agricultural extension officers providing the technical expertise to farmers and recommending the optimal application rates, etc.”

This conflict of interest in agro-dealers is one of the reasons for the overuse of fertilizer in some developing countries, according to Greenpeace.

The Greenpeace report ends with the following recommendations:

• Stop the practice of over-using fertilizers in intensive agriculture
• Phase out fertilizer subsidies
• Implement and enforce national fertilizer reduction policies that define maximum nitrogen applications per area

Read the Greenpeace report “Nitrates in drinking water in the Philippines and Thailand.”

Household and industrial waste have turned our bodies of water into toxic soups, according to an i Report feature by medical toxicologist Dr. Kenneth Hartigan-Go.

Greenpeace has already warned of an inevitable water crisis, saying that the quality of fresh water sources is steadily declining while the costs of obtaining clean water is rising.