Issues in Ecology Number 12 Summer 2004 Among the new organic contaminants of greatest concern the greatest concern PBDes areused in thousands of consume are synthetic musk fragrances,PBDE flame retardants,and products from fire-resistant textiles and upholstered fumiture to fluorinated surfactants. computers and televisions.Global demand for theseadditives Synthetic Fragrances.Syntheticmusk fragrances aresemi increased from 40,000 tons in 1992 to 67,125 tons in 1999. Theteta-andpertaBDEsTeEandne DE)are of greates wildlife TeBDE and PeBDE a icals writh erties similar to those of some PCBs.A highe synthetic fragrances areon the U.S.HPVC list but haveonly recently been studied as contaminants in any natural systemin solid phase hemical,but it may degrade in sunlight and in the ragrances used are edia form eks knov HHCB em adian A 0f1981to200.2 Flugrinated surfactants scientists have recently documented four synthetic compo nds wereproduced in19 for useas widespread contamination of wildlifeand the general human ds ted isa term early 21 ns of synth be organic mole me sin th n bonds.Th compounds.Recent measurements of the econ pounds in s region, chr disruption in fish.(Hormonally actives chemical that mimicor interfere with hormone function and can distort properties of perfluorinat ce I era rey ted anon sphys mu d PF the polveyclic musk fragrance AHINalld n dis ent.Worldwide diss nination of perfluorinated acids must therefore oour by way xylene were effectively banned from use as fragrances in 2002 of an airbomeneutral derivative that yields the free acid wheni U.S.HPV Wi espread detection of precursors of PFOSand their ngev h heUnited Sta m n nds ha aha y whic donot havetorenort how much thevuse ormanufacture.They also donot have to report any estimates on how much synthetic fragrance may ultimately be discharged into theenvironmen PFOS has been detected in the blood of ringed seals from the eco mpacts of s cond of n rthern f a,d cts of the nds in Eu in polar bear livers range fron wtweight.makniheanhaogn ram o for these fragrances. contaminant in these mammals.? duct n ve me chemicals as pote Mercury fateand in methodology,especially in the caseof fluorinated organics. globalpollutant and can bemobilized into the atmosphere from many human activities,including municipal trash incineratior ppagtpo burning of high sulfu coal (whic5 Issues in Ecology Number 12 Summer 2004 Among the new organic contaminants of greatest concern are synthetic musk fragrances, PBDE flame retardants, and fluorinated surfactants. Synthetic Fragrances. Synthetic musk fragrances are semi￾volatile and lipophilic (literally “fat-loving” because they are attracted to fatty tissues) compounds that are added to a wide range of personal care products, including perfumes, cosmetics, soaps, and shampoos as well as laundry detergents.15 These synthetic fragrances are on the U. S. HPVC list but have only recently been studied as contaminants in any natural system in this country. The most common synthetic fragrances used are two nitro musks called musk xylene and musk ketone and two polycyclic musks known as HHCB (hexahydro￾hexamethylcyclopentabenzopyran) and AHTN (hexamethyl￾tetraline). In Europe, approximately 6,500 metric tons of these four synthetic compounds were produced in 1999 for use as consumer product additives.16 In the early 1980s, concentrations of synthetic musk fragrances were discovered in animal tissues for the first time. Since then, there has been an increasing awareness of the ubiquitous distribution and possible toxicological effects of these compounds. Recent measurements of these compounds in wastewater effluent and in air and water in the Great Lakes region, for instance, have illustrated that ecological exposures are chronic and likely to be increasing.17 This is cause for concern because both HHCB and AHTN have been shown to exhibit hormonal disruption in fish.18 (Hormonally active substances are chemicals that mimic or interfere with hormone function and can distort normal reproductive development, alter behavior, and impair disease resistance in wildlife and humans.) Several studies with cell cultures indicate that musk xylene, musk ketone, p-amino￾musk xylene (a major breakdown product of musk xylene), and the polycyclic musk fragrance AHTN all demonstrate estrogenic activity in laboratory tests.In Europe, musk ketone and musk xylene were effectively banned from use as fragrances in 2002 because of their reported toxicities.19 Although HHCB and AHTN are both on the U. S. HPVC list, their use in personal care and household products is privileged information in the United States, and companies that use them do not have to report how much they use or manufacture. They also do not have to report any estimates on how much synthetic fragrance may ultimately be discharged into the environment. Because of this, ecological impacts of these compounds can only be identified through field and toxicological studies conducted long after exposures have begun. Fortunately, thanks to the intense interest in the fate and impacts of these compounds in Europe, analytical methods have been developed and standards are available for these fragrances. For the vast majority of high production volume chemicals identified as potentially bioaccumulative and persistent, however, there are no trace analytical methods available for tracking their fate and impacts.20 Many of the recently initiated measurements of organic chemicals have been made using advances in analytical methodology, especially in the case of fluorinated organics. Flame retardants. Among the newly emerging chemical contaminants of aquatic environments, the PBDE flame retardants and the perfluorinated surfactants discussed below have generated the greatest concern. PBDEs are used in thousands of consumer products from fire-resistant textiles and upholstered furniture to computers and televisions. Global demand for these additives increased from 40,000 tons in 1992 to 67,125 tons in 1999.21 The tetra- and pentaBDEs (TeBDE and PeBDE) are of greatest concern, and their concentrations are increasing in humans and wildlife.22 TeBDE and PeBDE are multimedia chemicals with physical properties similar to those of some PCBs. A higher brominated product, decabromodiphenyl ether (DecaBDE), is a solid phase chemical, but it may degrade in sunlight and in the tissues of fish to these lower brominated multimedia forms.23 Researchers measured a nine-fold increase in PBDEs in the tissues of ringed seals from the western Canadian Arctic over the period of 1981 to 2000.24 Fluorinated surfactants.Scientists have recently documented widespread contamination of wildlife and the general human population with perfluorinated acids.25 “Perfluorinated” is a term used to describe organic molecules that are fully fluorinated, meaning fluorine atoms have replaced all hydrogen atoms in the carbon-hydrogen bonds. The most widely known perfluorinated acids are perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA); however, similar compounds having longer or shorter perfluorinated chains are also produced or exist as impurities within manufactured formulations. These important industrial chemicals fall into the category of surfactants because they are surface￾active agents that repel water and oil or resist heat or other chemicals. The major use of PFOS is in treating fabric surfaces for stain resistance. The existing database describing physical properties of perfluorinated acids, including PFOS and PFOA, is severely limited because of their anomalous physical and chemical behavior. The properties of PFOS and PFOA suggest that they are poor candidates for long-range airborne transport, yet they have been discovered throughout the global environment. Worldwide dissemination of perfluorinated acids must therefore occur by way of an airborne neutral derivative that yields the free acid when it degrades.26 Widespread detection of precursors of PFOS and PFOA in the air in North America is providing increasing evidence that this is indeed the means by which these nonvolatile compounds have become such widespread contaminants.27 Over the past decade, researchers have found PFOS in birds, fish, and marine and land mammals around the world. For example, PFOS has been detected in the blood of ringed seals from the northern Baltic Sea, the eastern Canadian arctic, and Svalbard; the blood and liver of northern fur seals from Alaska; and the livers of polar bears from northern Alaska.28 PFOS concentrations in polar bear livers range from 1 to 5 micrograms per gram of tissue (wet weight), making it the most prominent organohalogen contaminant in these mammals.29 Mercury Mercury is a metallic element (Hg) that has been extracted for centuries from sulfide ore or cinnabar (HgS). It has become a global pollutant and can be mobilized into the atmosphere from many human activities, including municipal trash incineration, burning of high sulfur coal (which contains cinnabar) in coal￾fired power plants, metal smelting, chlorine-alkali plants, cement