An Assessment of Toxic Substances Pollution in the Hong Kong Marine Environment

ABSTRACT

The Environmental Protection Department (EPD) of the Hong Kong Special Administrative Region Government (HKSARG) commissioned a consultancy study in 1999 to better understand the potential sources, fates, and existing pollution state of toxic substances in Hong Kong's marine environment. A desk-top survey and assessment was first performed on a comprehensive initial list of 556 toxic substances. A Preliminary Priority Toxic Substances List (PPTSL) of 135 chemicals was established, consisting of heavy metals, inorganic compounds, organo-metallic compounds, and trace organics. A territory-wide baseline field sampling and laboratory analysis exercise was then undertaken during 2001–2002 to determine the level of these PPTSL chemicals in the potential pollution sources (effluent discharges, stormwater discharges, air deposition) and the receiving marine environment (water, sediment, biota). A draft Priority Toxic Substances List (PTSL) was developed, taking into account chemicals detected in the local marine environment and those listed under the Stockholm Convention, the Rotterdam Convention, and the International Maritime Organization's Harmful Antifouling System Convention. The draft PTSL chemicals were subject to ecological and incremental human health risk assessments. Based on the risk assessment results, 17 Chemicals of Potential Concern (COPC) for Hong Kong's marine environment were identified, most of which were heavy metals in the sediment. The study findings suggest that Hong Kong's marine environment is not widely polluted with chemicals present at concentrations of toxicological concern. Although a number of potentially problematic pollutants (COPC) were identified, they are confined to a few “hot spots” and are unlikely to pose a territory-wide risk. Based on the study recommendations, the EPD initiated in 2004 a toxic substances monitoring program to keep the COPC in the marine environment under close surveillance.

Key Words:

• toxic substances
• marine environment
• field baseline survey
• ecological and human health risk assessment
• pollution evaluation
• chemicals of potential concern
• Hong Kong.

ACKNOWLEDGMENTS

The authors thank the Director of the Environmental Protection Department of the Hong Kong Special Administrative Region (SAR) Government for his permission to publish the data collected in the consultant study (Agreement No. CE 22/99) commissioned to CH2M-IDC Hong Kong Limited in 1999. The opinions in this article are those of the authors and do not necessarily reflect the policy or views of the Hong Kong SAR Government.