Ambient Air Monitoring Data Comments AUGUST 26, 2007
Mark Cherniak, Ph.D. Science for Citizens |
Berkeley Citizen, August 26, 2007
Berkeley, California
You requested that I interpret ambient air quality monitoring data obtained from May, June, July, and August 2007, in the vicinity of the Pacific Steel Casting (PSC) facility in West Berkeley. The data you obtained reveals unsafe ambient air levels of manganese and nickel. Please see the attached spreadsheet.
In particular, manganese levels at 700 block of Gilman Street were 4-5 times the World Health Organization’s guideline value for this contaminant; nickel levels at this location were 180-220 times the U.S. EPA reference concentration for this contaminant. Manganese levels at 600 block of Gilman Street and 1300 block of 3rd Street were 10-20 times the World Health Organization’s guideline value for this contaminant; nickel levels at these locations were up to 330 times the U.S. EPA reference concentration for this contaminant.
All the above-mentioned levels of manganese and nickel also exceed the less stringent Chronic Reference Exposure Levels for these contaminants established by the California Office of Environmental Heath Hazard Assessment (OEHHA). The data set we have involves multiple 24-hour samples taken several weeks or months apart. That allows us to draw a much stronger inference that the 24-hour samples are representative of long-term conditions. The onus is on the company and/or the regulators to show that the 24-hour samples in the data set are not representative of long-term conditions.
There are several data suggesting that PSC is the source of these excessive levels of contaminants.
First, PSC is known to emit manganese and nickel: 691.3 pounds of manganese and 55.8 pounds of nickel in 2005 according to government agency data. At the locations where monitoring found excessive levels of both manganese and nickel, manganese levels exceeded nickel levels similar to PSC’s emissions of these contaminants.
Second, the California Air Resources Board banned the use of manganese additives in gasoline in 1976. It is highly unlikely that, more than 30 years later, appreciable levels of manganese are being re-suspended by vehicle traffic.
Third, manganese and nickel levels were highest at locations closest to and downwind from the PSC facility. The highest levels of manganese and nickel were obtained approximately one-tenth of a mile NE of PSC (the closest of all the sampling locations) at a time when prevailing winds were generally towards this location from PSC. In contrast, the lowest levels of manganese and nickel were obtained at 160 University Avenue, approximately 1.1 miles S-SW of PSC (the furthest of all the sampling locations) at a time when prevailing winds were generally from this location towards PSC.
I hope this is helpful in your use of this data.
Ambient Air Monitoring Data Comments OCTOBER !8, 2007
Mark Cherniak, Ph.D. Science for Citizens |
Berkeley Citizen, October 18, 2007
Berkeley, California
You requested that I interpret new ambient air quality monitoring data obtained in August and September 2007 in the vicinity of the Pacific Steel Casting (PSC) facility in West Berkeley. The data you obtained reveals unsafe ambient air levels of manganese and nickel. Please see the attached spreadsheet, which summarizes new and previously obtained data. Please read this letter in conjunction with my letter of August 26th, 2007, which summarizes the previously obtained data.
In brief, the new data continue the trend apparent in the previously obtained data of manganese and nickel levels that are excessive at locations in relatively close proximity to the PSC facility. As indicated by red boxes, six of the seven new manganese measurements exceed the U.S. EPA reference concentration of 0.05 mg/m3. Three of the seven new nickel measurements exceed the WHO guideline value for nickel of 0.00038 mg/m3.
Furthermore, the totality of the data is now more indicative of long-term (chronic) exposures in the vicinity of the PSC facility. Since you first began collecting data in May 2007 and up until the early September 2007 (twenty measurements spanning a period of three-and-a-half months), manganese levels at locations within 0.5 miles of the PSC facility have averaged 0.21 mg/m3 – above the California Office of Environmental Health Hazard Assessment’s (OEHHA) chronic inhalation Reference Exposure Level for manganese of 0.20 mg/m3. It is possible that persons living within this distance from the PSC facility have increased risk of health effects associated with chronic exposure to manganese, including impairment of neurobehavioural function as identified by the OEHHA.
In addition, I wish to add a point regarding the identity of the source of excess manganese and nickel levels that I omitted in my letter of August 26th, 2007: On August 1st-2nd, air samples were taken simultaneously using similar equipment at two locations: a location in close proximity to PSC (1306 3rd Street) and a location at a considerable distance (160 University Street) from PSC. However, both locations are subject to considerable vehicle traffic. The air sample from 306 3rd Street had high manganese levels whereas the air sample from 160 University Street had non-detectable manganese levels. This data would support the premise that PSC is the source of excess manganese levels in its vicinity and counter the premise that vehicle traffic is the source.
I hope this is helpful in your use of this data.
Mark Chernaik, Ph.D.
2355 Dale Avenue
Eugene, Oregon
