"We call on poultry and piggery owners to put premium on pollution control and wastewater treatment facilities to ensure that the wastes generated by their operations will not affect the surrounding environment and the health of the people in their respective communities," DENR Secretary Ramon J. P. Paje said.

Mr Paje issued the call amid complaints against some poultry and hog raisers about their untreated sewage spilling into rivers and other bodies of water, a violation of RA 9275, also known as the Clean Water Act of 2004.

"Farm owners should immediately employ corrective measures so as not to aggravate the situation," Mr Paje said.

The DENR chief warned continued violation of the clean air and water laws may result in permanent closure of erring poultry and piggery farms, a scenario which Mr Paje said he does not want to happen.

"We do not want to close poultry and piggery farms because it will create more problems like dwindling supply of eggs, chicken and pork, soaring prices etc," he said.

However, Mr Paje said that while the DENR recognizes the contribution of the chicken and hog industry to agricultural production and to the Philippine economy, this does not give them the license to pollute the water and air.

According to statistics, the overall production of hog and chicken in 2011 amounted to 1.94 million and 1.41 million metric tons, respectively.

"Based on our analysis, these industries, hog and chicken, just like in other countries, are very sustainable," Mr Paje said. "These are commercially viable industries that should invest in waste treatment facilities and other mitigating measures to control emission of gases and foul odor."

Mr Paje said the DENR would be willing to provide free technical assistance to farm owners in putting up wastewater treatment facilities.

As to foul odor, Mr Paje suggested poultry and hog raisers to frequently clean their area to contain animal manure and minimize odor.

Studies showed that livestock houses are one of the sources of particulate matter (PM), a kind of pollution that is small enough to be suspended in the atmosphere.

PM is made up of a number of components including acids, organic chemicals, metals, solid or dust particles which when inhaled can affect the heart and lungs.

Aside from PM, livestock farms emit gases such as ammonia, carbon dioxide, methane and nitrous oxide which contribute to global warming and are dangerous to human health.

Likewise, livestock production impacts the surrounding environment through surface and ground water contamination, air quality, and unpleasant odors emitted from the farms.