In 2006, Massachusetts became the first state in the nation to promulgate drinking water and waste site cleanup standards for perchlorate, a contaminant that was previously unregulated by any state or the federal government. MassDEP engaged stakeholders in this groundbreaking effort to gather and exchange information on perchlorate sources, occurrence, health risks, analytical monitoring methods and treatment techniques. Based on this information, MassDEP established a drinking water standard of two (2) parts per billion (ppb) for this emerging contaminant in 2006. The following year, MassDEP continued to consult with stakeholders about addressing other emerging contaminants, which led to the establishment of an Emerging Contaminant Workgroup. These proactive state initiatives are aimed at identifying new potential public health and environmental problems, and providing a process for deciding if and how MassDEP can or should address them.

Priority Contaminants & Status Reports

This list contains both those contaminants that MassDEP initially targeted in 2007 and continues to work on, as well as other contaminants the agency has identified since as requiring its attention.

  • 1,4-Dioxane
    Newly identified as a contaminant of emerging concern in July 2013, this heterocyclic compound is used mainly as a solvent or solvent stabilizer.
  • Cyanobacteria (Blue Green Algae)
    Also newly identified as an emerging contaminant in July 2013, these bacteria produce toxins which accumulate in water, and in high concentrations can even kill animals and people.
  • Methyl Tertiary Butyl Ether (MTBE)
    MTBE is an organic compound once widely used as a gasoline additive. Since petroleum refiners no longer use MTBE, no further action is needed.
  • Nanoparticles
    There are a wide variety of potential biomedical, electronic, optical and other applications for these tiny particles that are about one-billionth of a meter in size.
  • Perchlorate
    Perchlorate salts, derived from perchloric acid, are used extensively in fireworks.
  • Pharmaceuticals, Personal Care Products & Endocrine Blocking Compounds
    Although cosmetics and drugs have been used and prescribed for centuries, advances in scientific detection have only recently raised concerns about the presence of these chemicals in the environment.
  • Polybrominated Diphenyl Ethers (PBDEs)
    PDBEs are organobromide compounds used as flame retardants.
  • RDX or Royal Demolition Explosive (Cyclotrimethylenetrinitramine)
    This nitroamine compound was widely used by the military during World War II. MassDEP has established cleanup standards in 310 CMR 40.0000: The Massachusetts Contingency Plan (MCP).
  • Tetrachloroethylene (PCE)
    Often referred to as Perc, this chlorocarbon is widely used in the dry cleaning industry.
  • Trichloroethylene (TCE)
    This chlorinated hydrocarbon is commonly used as an industrial solvent.

For More Information

Contact Carol Rowan West, Director of the MassDEP Office of Research & Standards, at or 617-292-5510.