Measurements of chemical contaminants in caged (transplanted) and resident mussel populations have become a routine tool for monitoring and assessing the status and trends of coastal water quality. However, few long-term data sets are available to assess the comparability and efficacy of these two monitoring approaches. Three long-term independent data sets exist for Boston Harbor: the National Mussel Watch program has analyzed resident blue mussels (Mytilus edulis) from the Boston Harbor/Massachusetts Bay region for over twenty years, the Massachusetts Water Resources Authority has annually deployed caged (transplanted) mussels (Mytilus edulis) to assess bioaccumulation potential of sewage effluent discharged under its NPDES permit for over fourteen years, and the GulfWatch program has analyzed resident blue mussel populations for over twelve years. Together, these data provide consistent and comparable information on temporal and spatial changes in chemical contamination in Boston Harbor as steps were taken to reduce contaminant loading. The data also demonstrate the complementary nature of resident and caged (transplanted) mussels for assessing contaminant trends even when the basic approaches and sampling frequency differ. These fifteen year data sets demonstrate contaminant concentrations in mussels from Boston Harbor are similar and with few exceptions have significantly decreased since the early 1990s. The observed trends also demonstrate broad scale improvements to the quality of Boston Harbor and expand understanding of the response of coastal systems to interventions that reduce the load of chemicals to the ocean.Keywords: Mussel Watch, NOAA, GulfWatch, Status and Trends, caged mussels, The long-term data from the Mussel Watch program from 1986 through 2005 also reveal national, regional and local trends (Kimbrough et al., 2008). One of the local areas that received significant national attention in the late 1980s is Boston Harbor. Since then the Massachusetts Water Resources Authority (MWRA), the agency responsible for water supply and treatment of sewage for metropolitan Boston has completed several facility upgrades that improve the quality of sewage discharged to this system. These include termination of sewage sludge discharge in 1991, construction and operation of advanced primary treatment facilities since 1995, completing of advanced secondary treatment facilities in 2002, and relocation of the sewage effluent discharge 9.5 miles offshore in Massachusetts Bay (Werme and Hunt 2006;Rex et al. 2002). Over 95 percent of the sewage discharged from this outfall receives secondary treatment.The MWRA has also monitored the waters and sediments of Boston Harbor and Massachusetts Bay for trends in anthropogenic and other chemicals since the early 1990s (Tucker et al. 2006, Maciolek et al. 2006, Taylor 2005. Several studies have documented major improvements to the water and sediment quality , Bothner and Butman 2007, Zago et al. 2001, Bothner et al. 1998. One element of this long-term monitoring ...

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In rodent bioassays where chemicals are administered in the drinking water, water consumption data for individual animals are needed to estimate chemical exposures accurately. If multiple animals share a common water source, as occurs in some studies, only the total amount of drinking water consumed by all animals utilizing the common source is directly measurable, and water consumption rates for individual animals are not available. In the Four Lab Study of the US Environmental Protection Agency, which included a multigenerational rodent bioassay, a complex mixture of drinking water disinfection by-products was delivered to multiple Sprague-Dawley rats from a common drinking water container. To estimate disinfection by-product mixture exposure for each animal, authors developed four log-linear regression models to allocate water consumption among rats sharing a common water container. The four models represented three animal lifestages: Gestation, Lactation, and Postweaning, with separate Postweaning models for male and female. Authors used data from six Sprague-Dawley rat bioassays to develop these models from available individual cage data for the Postweaning models, and available individual animal data for the Gestation and Lactation models. The r(2) values for the model fits were good, ranging from 0.67 to 0.92. The Gestation and Lactation models were generally quite accurate in predicting average daily water consumption whereas the Postweaning models were less robust. These models can be generalized for use in other reproductive and developmental bioassays where common water sources are used and data on the explanatory variables are available.

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Due to its high efficiency and superior durability, the diesel engine is again becoming a prime candidate for future light-duty vehicle applications within the United States. While in Europe the overall diesel share exceeds 40%, the current diesel share in the United States is 1%. Despite the current situation and the very stringent Tier 2 emission standards, efforts are being made to introduce the diesel engine back into the U.S. market. In order to succeed, these vehicles have to comply with emissions standards over a 120,000 miles distance while maintaining their excellent fuel economy. The availability of technologies-such as high-pressure, common-rail fuel systems; low-sulfur diesel fuel; oxides of nitrogen (NO x ) adsorber catalysts or NACs; and diesel particle filters (DPFs)-allow the development of powertrain systems that have the potential to comply with the light-duty Tier 2 emission requirements. In support of this, the U.S. Department of Energy (DOE) teamed with industry to engage in several testing projects under the Advanced Petroleum Based FuelsDiesel Emission Controls (APBF-DEC) activity [1; 2; 5; 6; 7; 8]. Three of the APBF-DEC projects evaluated the sulfur tolerance and durability of NAC/DPF systems on various platforms, and one evaluated the performance and durability of a selective catalytic reduction (SCR) system in heavy-duty engines.A fifth project investigated the effects of oil properties on the performance and durability of a NAC.This project investigated the performance of the emission control system and system desulfurization effects on regulated and unregulated emissions in a light-duty diesel engine. Emissions measurements were conducted over the Federal Test Procedure (FTP), the US06 [an aggressive chassis dynamometer emissions test procedure, part of the Supplemental Federal Test Procedure (SFTP)], and the Highway Fuel Economy Test (HFET). Testing was conducted after the accumulation of 150 hours of engine operation calculated to be the equivalent of approximately 8,200 miles. For these evaluations, three out of six of the FTP test cycles were within the 50,000-mile Tier 2 bin 5 emission standards [0.05 g/mi NO x and 0.01 g/mi particulate matter (PM)]. Emissions over the SC03 (airconditioning test) portion of the SFTP were within limits of the 4,000-mile SFTP standards. Emissions of NO x +NMHC (non-methane hydrocarbons) exceeded the 4,000-mile SFTP standards over the US06 portion of the SFTP. Testing was also conducted after the accumulation of 1,000 hours of engine operation calculated to be the equivalent of approximately 50,000 miles. The results were reported in [7] 2005-01-1755. Recalibrated drivability maps resulted in more repeatable NO x emissions from cycle to cycle. The NO x level was below the Tier 2 emission limits for 50,000 and 120,000 miles. NMHC emissions were found at a level outside the limit for 120,000 miles.