Timber bridges provide an economical alternative to concrete and steel structures, particularly in rural areas with light to moderate vehicle traffic. Wooden components of these bridges are treated with chromated copper arsenate type C (CCA), pentachlorophenol, or creosote to prolong the life of the structure from a few years to many decades. This results in reduced transportation infrastructure costs and increased public safety. However, the preservative used to treat the wooden components in timber bridges is lost to the environment in small amounts over time. This report describes the concentration of wood preservatives lost to adjacent environments and the biological response to these preservatives as environmental contaminants. Six bridges from various states were examined for risk assessment: two creosote treated bridges, two pentachlorophenol-treated bridges, and two CCA-treated bridges. In all cases, the largest bridges located in biologically active environments associated with slow-flowing water were selected to represent worst-case analyses. Sediment and water column concentrations of preservative were analyzed upstream from, under, and downstream from each bridge. The observed levels of contaminant were compared with available regulatory standards or benchmarks and with the quantitative description of the aquatic invertebrate community sampled from vegetation and sediments. Pentachlorophenol- and creosote-derived polycyclic aromatic hydrocarbons (PAHs) were not observed in the water near any of the selected bridges. However, low levels of PAHs were observed in the sediments under and immediately downstream from these bridges. Pentachlorophenol concentrations did not approach toxicological benchmarks. Sediment concentrations of naphthalene, acenaphthylene, and phenanthrene exceeded the probable effect level. Metal levels at the bridges treated with CCA were less than predicted effect levels, in spite of questionable construction practices. Adverse biological effects were not observed in the aquatic invertebrate community or laboratory bioassays conducted on water and sediments sampled at each of the bridges. Results of this study reveal the need to follow the construction information found in Best Management Practices for the Use of Treated Wood In Aquatic Environments published by Western Wood Preservers Institute. Regulatory benchmarks used in risk assessments of this type need to be indexed to local environmental conditions. The robust invertebrate communities associated with slow-moving streams over soft bottoms were not susceptible to the concentrations of PAHs that would be expected to affect more sensitive taxa, which typically are located in faster moving water over hard bottoms. Contaminants released from timber bridges into these faster systems (where more sensitive taxa are located) are significantly diluted and not found at biologically significant levels.

On cover: IPCS International Programme on Chemical Safety. Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organization and the World Health Organization, and produced within the framework of the Inter-organization Programme for the Sound Management of Chemicals (IOMC)

The New York Times bestselling book that takes you inside SEAL Team Six – the covert squad that killed Osama Bin Laden SEAL Team Six is a secret unit tasked with counterterrorism, hostage rescue, and counterinsurgency. In this dramatic, behind-the-scenes chronicle, Howard Wasdin takes readers deep inside the world of Navy SEALS and Special Forces snipers, beginning with the grueling selection process of Basic Underwater Demolition/SEAL (BUD/S)—the toughest and longest military training in the world. After graduating, Wasdin faced new challenges. First there was combat in Operation Desert Storm as a member of SEAL Team Two. Then the Green Course: the selection process to join the legendary SEAL Team Six, with a curriculum that included practiced land warfare to unarmed combat. More than learning how to pick a lock, they learned how to blow the door off its hinges. Finally as a member of SEAL Team Six he graduated from the most storied and challenging sniper program in the country: The Marine's Scout Sniper School. Eventually, of the 18 snipers in SEAL Team Six, Wasdin became the best—which meant one of the best snipers on the planet. Less than half a year after sniper school, he was fighting for his life. The mission: capture or kill Somalian warlord Mohamed Farrah Aidid. From rooftops, helicopters and alleys, Wasdin hunted Aidid and killed his men whenever possible. But everything went quickly to hell when his small band of soldiers found themselves fighting for their lives, cut off from help, and desperately trying to rescue downed comrades during a routine mission. The Battle of Mogadishu, as it become known, left 18 American soldiers dead and 73 wounded. Howard Wasdin had both of his legs nearly blown off while engaging the enemy. His dramatic combat tales combined with inside details of becoming one of the world's deadliest snipers make this one of the most explosive military memoirs in years.

This volume offers a meta-philosophical reflection on feminist philosophies of science. It emphasizes and discusses both the connections and differences between "traditional" philosophies of science and feminist philosophies of science. The collection systematically analyses feminist contributions to the various philosophies of specific sciences. Each chapter is devoted to a specific area of philosophy of science: general philosophy of science, philosophy of biology, philosophy of climate sciences, philosophy of cognitive sciences and neurosciences, philosophy of economics, philosophy of history and archaeology, philosophy of logic and mathematics, philosophy of medicine, philosophy of psychology, philosophy of physics, and philosophy of social sciences. Since some of these areas have so far rarely been addressed by feminist philosophers, this new collection provides new angels and stimulates the debate on pivotal issues that are part and parcel of both "traditional" philosophies of science and feminist philosophies of science. Using a range of different methodologies and styles, the essays all show great clarity in both arguments and contents.