Dolomite by the bay: all right or not right?

Published September 12, 2020, 3:20 PM

by Dr. Kaycee Reyes

Assessing the health risks of the latest Manila Bay project 

White sand on Manila Bay? Yes, says the Department of Natural Resources (DENR), as its Manila Bay Rehabilitation Project was launched last year with the purpose to improve water quality, rehabilitate and relocate informal settlers, and to educate citizens and sustain law enforcement and monitoring. DENR’s decision to enhance the aesthetic of the popular tourist and local spot as part of the project, however, did not sit well with critics and environmentalists alike. Apparently, it is currently being contested not only for its untimely and unnecessary execution but also because the sand being layered is crushed dolomite, which environmentalists say is hazardous to the environment and to people’s health. While dolomite is not “real” white sand, does it actually pose a health risk?

Synthetic sand along the bay? Dolomite, or calcium magnesium carbonate, is a type of limestone that is used to produce cement, mortar, concrete, and other materials needed for construction.  According to DENR, their plan of using dolomite has already been studied for its safety even before its implementation and approval last year, clearing it from being hazardous or containing harmful chemicals as disputed by environmentalist groups. Material Safety Data Sheets from several international suppliers, manufacturers, and producers of construction materials such as Lehigh Hanson Inc. do state that dolomite contains crystalline silica in dust form (particles less than 10 micrometers in aerodynamic diameter) and may be harmful to respiratory health if taken in at an enormous amount.  A significant amount may cause coughing, shortness of breath, chest pains, or at the worst, even silicosis and cancer with constant exposure. The Department of Health (DOH) agrees too, that any type of dust, including dolomite, could lead to symptoms such as chest discomfort, shortness of breath, and coughing. The DOH, however, also notes that the crushed dolomite being layered on Manila Bay is two to five mm in size, or 100 times bigger than dust, and therefore does not pose such a risk. In addition, the DOH says that proper health and safety standards are being observed by workers, and that risks for dust formation are continuously monitored as well. As of this writing, environmental agencies, fisherfolk, and other critics are launching petitions to stop the layering of dolomite on Manila Bay. And to further manage opposing views, the DENR ordered another study to confirm once and for all if crushed dolomite is indeed safe or not.

Manila Bay, one with the most beautiful sunsets, has been deteriorating for decades. Its unsafe and uninhabitable waters have come from water pollution, toxic commercial, industrial and agricultural waste, sewerage problems, and congested canals, among others. Rehabilitation programs such as this, however, give hope for a cleaner and safer Manila Bay in the near future, and it is a good start that sectors continue being actively involved to ensure that marine life will be preserved and maintained and will flourish, while also not posing any risks to humans.

In saving Manila Bay, one thing remains clear: Protecting the environment and people’s health will always succeed with community effort.