Public Meeting: MDPH Activities in South Weymouth and Neighboring Communities
Bureau of Environmental Health Assessment
Massachusetts Department of Public Health
February 13, 2002

MDPH Investigation on Arsenic in South Weymouth
Bureau of Environmental Health Assessment
Massachusetts Department of Public Health
Status Report
February 13, 2001

MDPH Activities To Date
•	Collection of tap water from five homes of individuals who expressed concern about arsenic exposure
•	Testing of town drinking water supply including raw water samples
•	Indoor environmental sampling at several homes in South Weymouth
•	Soil sampling in public areas in South Weymouth and an offer to conduct soil sampling at certain private residences in South Weymouth 
•	Two public meetings in early and late summer last year
•	Coordination with the Mayor of Weymouth to have monthly testing of the town drinking water supply
•	Offered urinary arsenic testing to 70 households which included approximately 200 residents.

Factors Influencing Urinary Arsenic Concentrations
•	Many factors can influence urinary arsenic concentration: seafood consumption, existing illnesses, occupational exposures, environmental exposures, other dietary foods, herbal remedies
•	Commercial labs use background levels of 50 ug As/g creatinine.
•	MDPH used more conservative background level of 25 ug As/g creatinine.

Urinary Arsenic Testing
•	Offered to 70 households
o	63 households participated (90%)
•	184 individuals chose to participate in urinary arsenic testing
•	Samples collected in early October

Urine Testing Results
•	171 participants had no arsenic present in urine or less than 25 ug As/g creatinine
•	8 participants had levels greater than 25 ug As/g creatinine 
o	reported seafood consumption during 72 hours prior to sample collection
•	5 participants had levels slightly above 25 ug As/g creatinine (i.e. 26-32 ug As/g creatinine)
o	reported no consumption of seafood products

Re-testing Efforts
•	MDPH offered to re-test all individuals whose urinary arsenic level was greater than 25 ug As/g creatinine
•	Five people wanted to give a second urine sample to be analyzed for total arsenic
o	a 3 day food record was also obtained from these participants
•	Three additional urine samples from young children were collected after the initial sample collection.

Continuing Activities
•	Uniform environmental medicine evaluations of all members of six families 
•	Focused testing of the Great Pond reservoir

Great Pond Water and Sediment Sampling
•	Concerns have been expressed that sporadic elevations of arsenic in drinking water may result from various environmental conditions in the pond (e.g., spring and fall turnover) that may not be captured by testing required by drinking water regulations
•	Sediment and surface water samples will be taken four times during the course of one year, including during spring and fall turnover events, at five locations depicted on the picture

Figure: Proposed Sediment and Surface Water Sample Locations for Great Pond Weymouth, MA

Great Pond Water and Sediment Sampling
•	In addition, raw drinking water samples (i.e., prior to treatment) will be taken every other week for one year to gather data on arsenic concentrations of water entering the treatment system directly from the intake at Great Pond
•	Draft protocol has been submitted to ATSDR and is being reviewed by others (e.g., MDEP, environmental engineer working on behalf of a South Weymouth family, US Geological Survey)