McKay, Donald. "Environmental Chemicals and Their Properties" Multimedia Environmental Models Edited by Donald McKay Boca Raton: CRC Press LLC,2001 ©2001 CRC Press LLC CHAPTER 3 Environmental Chemicals and Their Properties 3.1 INTRODUCTION AND DATA SOURCES In this book, we focus on techniques for building mass balance models of chemical fate in the environment, rather than on the detailed chemistry that controls transport and transformation, as well as toxic interactions. For a fuller account of the basic chemistry, the reader is referred to the excellent texts by Crosby (1988), Tinsley (1979), Stumm and Morgan (1981), Pankow (1991), Schwarzenbach et al. (1993), Seinfeld and Pandis (1997), Findlayson-Pitts and Pitts (1986), Thibodeaux (1996), and Valsaraj (1995). There is a formidable and growing literature on the nature and properties of chemicals of environmental concern. Numerous handbooks list relevant physical- chemical and toxicological properties. Especially extensive are compilations on pesticides, chemicals of potential occupational exposure, and carcinogens. Govern- ment agencies such as the U.S. Environmental Protection Agency (EPA), Environ- ment Canada, scientific organizations such as the Society of Environmental Toxi- cology and Chemistry (SETAC), industry groups, and individual authors have published numerous reports and books on specific chemicals or classes of chemicals. Conferences are regularly held and proceedings published on specific chemicals such as the “dioxins.” Computer-accessible databases are now widely available for consultation. Table 3.1 lists some of the more widely used texts and scientific journals. Most are available in good reference libraries. Most of the chemicals that we treat in this book are organic, but the mass balancing principles also apply to metals, organometallic chemicals, gases such as oxygen and freons, inorganic compounds, and ions containing elements such as phosphorus and arsenic. Metals and other inorganic compounds tend to require individual treatment, because they usually possess a unique set of properties. Organic compounds, on the other hand, tend to fall into certain well defined classes. We are often able to estimate the properties and behavior of one organic chemical from that ©2001 CRC Press LLC Table 3.1 Sources of information on chemical properties and estimation methods (See Chapter 1.5 of Mackay, et al., Illustrated Handbooks of Physical Chemical Properties and Environmental Fate for Organic Chemicals, cited below, for more details) The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals (Annual), S. Budavarie, ed. Whitehouse Station, NJ: Merck & Co., 1996. Handbook of Chemistry and Physics, D. R. Lide, ed., 81/e. Boca Raton, FL: CRC Press. Verschueren’s Handbook of Environmental Data on Organic Chemicals. New York: John Wiley & Sons, 1997. Illustrated Handbook of Physical Chemical Properties and Environmental Fate for Organic Chemicals (in 5 volumes). D. Mackay, W. Y Shiu, and K. C. Ma. Boca Raton, FL: CRC Press, 1991–1997. Also available as a CD ROM. Handbook of Environmental Fate and Exposure Data for Organic Chemicals (several volumes), P. H. Howard, ed. Boca Raton, FL: Lewis Publications. Handbook of Environmental Degradation Rates, P. H. Howard et al. Boca Raton, FL: Lewis Publications. Lange’s Handbook of Chemistry , 15/e, J. A. Dean, ed. New York: McGraw-Hill, 1998. Dreisbach’s Physical Properties of Chemical Compounds, Vol I to III. Washington, DC, Amer. Chem. Soc. Technical Reports, European Chemical Industry Ecology and Toxicology Centre (ECETOC). Brussels, Belgium. Sax’s Dangerous Properties of Industrial Materials, 10/e. R. J. Lewis, ed. New York: John Wiley & Sons. Groundwater Chemicals Desk Reference, J. J. Montgomery. Boca Raton, FL: Lewis Publications, 1996. Genium Materials Safety Data Sheets Collection. Amsterdam, NY: Genium Publishing Corp. The Properties of Gases and Liquids, R. C. Reid, J. M. Prausnitz, and B. E. Poling. New York: McGraw-Hill, 1987. NIOSH/OSHA Occupational Health Guidelines for Chemical Hazards. Washington, DC: U.S. Government Printing Office. The Pesticide Manual, 12/e. C. D. S. Tomlin, ed. Loughborough, UK: British Crop Protection Council. The Agrochemicals Handbook, H. Kidd and D. R. James, eds. London: Royal Society of Chemistry. Agrochemicals Desk Reference, 2/e, J. H. Montgomery. Boca Raton, FL: Lewis Publications. ARS Pesticide Properties Database, R. Nash, A. Herner, and D. Wauchope. Beltsville, MD: U.S. Department of Agriculture, www.arsusda.gov/rsml/ppdb.html. Substitution Constants for Correlation Analysis in Chemistry and Biology, C. H. Hansch (currently out of print). New York: Wiley-Interscience. Handbook of Chemical Property Estimation Methods, W. J. Lyman, W. F. Reehl, D. H. Rosenblatt (currently out of print). New York: McGraw-Hill. Handbook of Property Estimation Methods for Chemicals, R. S. Boethling and D. Mackay. Boca Raton, FL: CRC Press, 2000. Chemical Property Estimation: Theory and Practice, E. J. Baum. Boca Raton, FL: Lewis Publications, 1997. Toolkit for Estimating Physiochemical Properties of Organic Compounds, M. Reinhard and A. Drefahl. New York: John Wiley & Sons, 1999. IUPAC Handbook. Research Triangle Park, NC: International Union of Pure and Applied Chemistry. Website for database and EPIWIN estimation methods, Syracuse, NY: Syracuse Research Corporation (http://www.syrres.com). ©2001 CRC Press LLC of other, somewhat similar or homologous chemicals. An example is the series of chlorinated benzenes that vary systematically in properties from benzene to hexachlorobenzene. It is believed that some 50,000 to 80,000 chemicals are used in commerce. The number of chemicals of environmental concern runs to a few thousand. There are now numerous lists of “priority” chemicals of concern, but there is considerable variation between lists. It is not possible, or even useful, to specify an exact number of chemicals. Some inorganic chemicals ionize in contact with water and thus lose their initial identity. Some lists name PCBs (polychlorinated biphenyls) as one chemical and others as six groups of chemicals whereas, in reality, the PCBs consist of 209 possible individual congeners. Many chemicals, such as surfactants and solvents, are complex mixtures that are difficult to identify and analyze. One des- ignation, such as naphtha , may represent 1000 chemicals. There is a multitude of pesticides, dyes, pigments, polymeric substances, drugs, and silicones that have valuable social and commercial applications. These are in addition to the numerous “natural” chemicals, many of which are very toxic. For legislative purposes, most jurisdictions have compiled lists of chemicals that are, or may be, encountered in the environment, and from these “raw” lists of chemicals of potential concern they have established smaller lists of “priority” chemicals. These chemicals, which are usually observed in the environment, are known to have the potential to cause adverse ecological and/or biological effects and are thus believed to be worthy of control and regulation. In practice, a chemical that fails to reach the “priority” list is usually ignored and receives no priority rather than less priority. These lists should be regarded as dynamic. New chemicals are being added as enthusiastic analytical chemists detect them in unexpected locations or toxicologists discover subtle new effects. Examples are brominated flame retardants, chlorinated alkanes, and certain very stable fluorinated substances (e.g., trifluoroacetic acid) that have only recently been detected and identified. In recent years, concern has grown about the presence of endocrine modulating substances such as nonylphenol, which can disrupt sex ratios and generally interfere with reproductive processes. The popular book Our Stolen Future, by Colborn et al. (1996) brought this issue to public attention. Some of these have industrial or domestic sources, but there is increasing concern about the general contamination by drugs used by humans or in agriculture. Table 3.2 lists about 200 chemicals by class and contains many of the chemicals of current concern. 3.2 IDENTIFYING PRIORITY CHEMICALS It is a challenging task to identify from “raw lists” of chemicals a smaller, more manageable number of “priority” chemicals. Such chemicals receive intense scrutiny, analytical protocols are developed, properties and toxicity are measured, and reviews are conducted of sources, fate, and effects. This selection contains an element of judgement and is approached by different groups in different ways. A common thread among many of the selection processes is the consideration of six factors: quantity, ©2001 CRC Press LLC Table 3.2 List of Chemicals Commonly Found on Priority Chemical Lists Volatile Halogentated Hydrocarbons Monoaromatic Hydrocarbons Chloromethane Benzene Methylene chloride Toluene Chloroform o-Xylene Carbontetrachloride m-Xylene Chloroethane p-Xylene 1,1-Dichloroethane Ethylbenzene 1,2-Dichloroethane Styrene cis-1,2-Dichloroethene trans-1,2-Dichloroethene Polycyclic Aromatic Hydrocarbons Vinyl chloride Naphthalene 1,1,1-Trichloroethane 1-Methylnaphthalene 1,1,2-Trichloroethane 2-Methylnaphthalene Tr ichloroethylene Trimethylnaphthalene Tetrachloroethylene Biphenyl Hexachloroethane Acenaphthene 1,2-Dichloropropane Acenaphthylene 1,3-Dichloropropane Fluorene cis-1,3-Dichloropropylene Anthracene trans-1,3-Dichloropropylene Fluoranthene Chloroprene Phenanthrene Bromomethane Pyrene Bromoform Chrysene Ethylenedibromide Benzo(a)anthracene Chlorodibromomethane Dibenz(a,h)anthracene Dichlorobromomethane Benzo(b)fluoranthene Dichlorodibromomethane Benzo(k)fluoranthene Freons (chlorofluoro-hydrocarbons) Benzo(a)pyrene Dichlorodifluoromethane Perylene Tr ichlorofluoromethane Benzo(g,h,i)perylene Indeno(1,2,3)pyrene Halogenated Monoaromatics Chlorobenzene 1,2-Dichlorobenzene Dienes 1,3-Dichlorobenzene 1,3-Butadiene 1,4-Dichlorobenzene Cyclopentadiene 1,2,3-Trichlorobenzene Hexachlorobutadiene 1,2,4-Trichlorobenzene Hexachlorocyclopentadiene 1,2,3,4-Tetrachlorobenzene 1,2,3,5-Tetrachlorobenzene Alcohols and Phenols Benzyl alcohol Phenol o-Cresol m-Cresol p-Cresol 2-Hydroxybiphenyl 4-Hydroxybiphenyl Eugenol ©2001 CRC Press LLC 1,2,4,5-Tetrachlorobenzene Halogenated Phenols Pentachlorobenzene 2-Chlorophenol Hexachlorobenzene 2,4-Dichlorophenol 2,4,5-Trichlorotoluene 2,6-Dichlorophenol Octachlorostyrene 2,3,4-Trichlorophenol 2,3,5-Trichlorophenol Halogenated Biphenyls and Naphthalenes 2,4,5-Trichlorophenol Polychlorinated Biphenyls (PCBs) 2,4,6-Trichlorophenol Polybrominated Biphenyls (PBBs) 2,3,4,5-Tetrachlorophenol 1-Chloronaphthalene 2,3,4,6-Tetrachlorophenol 2-Chloronaphthalene 2,3,5,6-Tetrachlorophenol Polychlorinated Naphthalenes (PCNs) Pentachlorophenol 4-Chloro-3-methylphenol Aroclor Mixtures (PCBs) 2,4-Dimethylphenol Aroclor 1016 2,6-Di-t-butyl-4-methylphenol Aroclor 1221 Tetrachloroguaiacol Aroclor 1232 Aroclor 1242 Nitrophenols, Nitrotoluenes Aroclor 1248 and Related Compounds Aroclor 1254 2-Nitrophenol Aroclor 1260 4-Nitrophenol 2,4-Dinitrophenol Chlorinated Dibenzo-p-dioxins 4,6-Dinitro-o-cresol 2,3,7,8-Tetrachlorodibenzo-p-dioxin Nitrobenzene Tetrachlorinated dibenzo-p-dioxins 2,4-Dinitrotoluene Pentachlorinated dibenzo-p-dioxins 2,6-Dinitrotoluene Hexachlorinated dibenzo-p-dioxins Heptachlorinated dibenzo-p-dioxins 1-Nitronaphthalene Octachlorinated dibenzo-p-dioxin 2-Nitronaphthalene Brominated dibenzo-p-dioxins 5-Nitroacenaphthalene Chlorinated Dibenzofurans Fluorinated Compounds Tetrachlorinated dibenzofurans Polyfluorinated alkanes Pentachlorinated dibenzofurans Trifluoroacetic acid Hexachlorinated dibenzofurans Fluoro-chloro acids Heptachlorinated dibenzofurans Polyfluorinated chemicals Octachlorodibenzofuran Phthalate Esters Nitrosamines and Other Nitrogen Compounds Dimethylphthalate N-Nitrosodimethylamine Diethylphthalate N-Nitrosodiethylamine Di-n-butylphthalate N-Nitrosodiphenylamine Di-n-octylphthalate N-Nitrosodi-n-propylamine Di(2-ethylhexyl) phthalate Diphenylamine Benzylbutylphthalate Indole 4-aminoazobenzene Chlorinated longer chain alkanes Pesticides, including biocides, fungicides, rodenticides, insecticides and herbicides Table 3.2 List of Chemicals Commonly Found on Priority Chemical Lists ©2001 CRC Press LLC persistence, bioaccumulation, potential for transport to distant locations, toxicity, and a miscellaneous group of other adverse effects. 3.2.1 Quantity The first factor is the quantity produced, used, formed or transported, including consideration of the fraction of the chemical that may be discharged to the environ- ment during use. Some chemicals, such as benzene, are used in very large quantities in fuels, but only a small fraction (possibly less than a fraction of a percent) is emitted into the environment through incomplete combustion or leakage during storage. Other chemicals, such as pesticides, are used in much smaller quantities but are discharged completely and directly into the environment; i.e., 100% is emitted. At the other extreme, there are chemical intermediates that may be produced in large quantities but are emitted in only minuscule amounts (except during an industrial accident). It is difficult to compare the amounts emitted from these various categories, because they are highly variable and episodic. It is essential, however, to consider this factor; many toxic chemicals have no significant adverse impact, because they enter the environment in negligible quantities. Central to the importance of quantity is the adage first stated by Paracelsus, nearly five centuries ago, that the dose makes the poison. This can be restated in the form that all chemicals are toxic if administered to the victim in sufficient quantities. A corollary is that, in sufficiently small doses, all chemicals are safe. Indeed, certain metals and vitamins are essential to survival. The general objective of environmental regulation or “management” must therefore be to ensure that the quantity of a specific substance entering the environment is not excessive. It need not be zero; indeed, it is impossible to achieve zero. Apart from cleaning up past mistakes, the most useful regulatory action is to reduce emissions to acceptable levels and thus ensure that concentrations and exposures are tolerable. Not even the EPA can reduce the toxicity of benzene. It can only reduce emissions. This implies knowing what the emissions are and where they come from. This is the focus of programs such as the Toxics Release Inventory (TRI) in the U.S.A. or the National Pollutant Release Inventory (NPRI) system in Canada. There are similar programs in Europe, Australia, and Japan. Regrettably, the data are often incomplete. A major purpose of this book is to give the reader the ability to translate emission rates into environmental concentrations so that the risk resulting from exposure to these con- centrations can be assessed. When this can be done, it provides an incentive to improve release inventories. 3.2.2 Persistence The second factor is the chemical’s environmental persistence, which may also be expressed as a lifetime, half-life, or residence time . Some chemicals, such as DDT or the PCBs, may persist in the environment for several years by virtue of their resistance to transformation by degrading processes of biological and physical origin. They may have the opportunity to migrate widely throughout the environment and reach vulnerable organisms. Their persistence results in the possibility of establishing ©2001 CRC Press LLC relatively high concentrations. This arises because, in principle, the amount in the environment (kilograms) can be expressed as the product of the emission rate into the environment (kilograms per year) and the residence time of the chemical in the environment (years). Persistence also retards removal from the environment once emissions are stopped. A legacy of “in place” contamination remains. This is the same equation that controls a human population. For example, the number of Canadians (about 30 million) is determined by the product or the rate at which Canadians are born (about 0.4 million per year) and the lifetime of Canadians (about 75 years). If Canadians were less persistent and lived for only 30 years, the population would drop to 12 million. Intuitively, the amount (and hence the concentration) of a chemical in the environment must control the exposure and effects of that chemical on ecosystems, because toxic and other adverse effects, such as ozone depletion, are generally a response to concentration. Unfortunately, it is difficult to estimate the environmen- tal persistence of a chemical. This is because the rate at which chemicals degrade depends on which environmental media they reside in, on temperature (which varies diurnally and seasonally), on incidence of sunlight (which varies similarly), on the nature and number of degrading microorganisms that may be present, and on other factors such as acidity and the presence of reactants and catalysts. This variable persistence contrasts with radioisotopes, which have a half-life that is fixed and unaffected by the media in which they reside. In reality, a substance experiences a distribution of half-lives, not a single value, and this distribution varies spatially and temporally. Obviously, long-lived chemicals, such as PCBs, are of much greater concern than those, such as phenol, that may persist in the aquatic environment for only a few days as a result of susceptibility to biodegra- dation. Some estimate of persistence or residence time is thus necessary for priority setting purposes. Organo-halogen chemicals tend to be persistent and are therefore frequently found on priority lists. Later in this book, we develop methods of calculating persistence. 3.2.3 Bioaccumulation The third factor is potential for bioaccumulation (i.e., uptake of the chemical by organisms). This is a phenomenon, not an effect; thus bioaccumulation per se is not necessarily of concern. It is of concern that bioaccumulation may cause toxicity to the affected organism or to a predator or consumer of that organism. Historically, it was the observation of pesticide bioaccumulation in birds that prompted Rachel Carson to write Silent Spring in 1962, thus greatly increasing public awareness of environmental contamination. As we discuss later, some chemicals, notably the hydrophobic or “water-hating” organic chemicals, partition appreciably into organic media and establish high con- centrations in fatty tissue. PCBs may achieve concentrations (i.e., they bioconcen- trate) in fish at factors of 100,000 times the concentrations that exist in the water in which the fish dwell. For some chemicals (notably PCBs, mercury, and DDT), there is also a food chain effect. Small fish are consumed by larger fish, at higher trophic levels, and by other animals such as gulls, otters, mink, and humans. These chemicals ©2001 CRC Press LLC may be transmitted up the food chain, and this may result in a further increase in concentration such that they are biomagnified. Bioaccumulation tendency is normally estimated using an organic phase-water partition coefficient and, more specifically, the octanol-water partition coefficient. This, in turn, can be related to the solubility of the chemical in the water. Clearly, chemicals that bioaccumulate, bioconcentrate, and biomagnify have the potential to travel down unexpected pathways, and they can exert severe toxic effects, especially on organisms at higher trophic levels. The importance of bioaccumulation may be illustrated by noting that, in water containing 1 ng/L of PCB, the fish may contain 10 5 ng/kg. A human may consume 1000 L of water annually (containing 1000 ng of PCB) and 10 kg of fish (containing 10 6 ng of PCB), thus exposure from fish consumption is 1000 times greater than that from water. Particularly vulnerable are organisms such as certain birds and mammals that rely heavily on fish as a food source. 3.2.4 Toxicity The fourth factor is the toxicity of the chemical. The simplest manifestation of toxicity is acute toxicity. This is most easily measured as a concentration that will kill 50% of a population of an aquatic organism, such as fish or an invertebrate (e.g., Daphnia magna ), in a period of 24–96 hours, depending on test conditions. When the concentration that kills (or is lethal to) 50% (the LC50) is small, this corresponds to high toxicity. The toxic chemical may also be administered to laboratory animals such as mice or rats, orally or dermally. The results are then expressed as a lethal dose to kill 50% (LD50) in units of mg chemical/kg body weight of the animal. Again, a low LD50 corresponds to high toxicity. More difficult, expensive, and contentious are chronic , or sublethal , tests that assess the susceptibility of the organism to adverse effects from concentrations or doses of chemicals that do not cause immediate death but ultimately may lead to death. For example, the animal may cease to feed, grow more slowly, be unable to reproduce, become more susceptible to predation, or display some abnormal behav- ior that ultimately affects its life span or performance. The concentrations or doses at which these effects occur are often about 1/10th to 1/100th of those that cause acute effects. Ironically, in many cases, the toxic agent is also an essential nutrient, so too much or too little may cause adverse effects. Although most toxicology is applied to animals, there is also a body of knowledge on phytotoxicity, i.e., toxicity to plants. Plants are much easier to manage, and killing them is less controversial. Tests also exist for assessing toxicity to microorganisms. It is important to emphasise that toxicity alone is not a sufficient cause for concern about a chemical. Arsenic in a bottle is harmless. Disinfectants, biocides, and pesti- cides are inherently useful because they are toxic. The extent to which the organism is injured depends on the inherent properties of the chemical, the condition of the organism, and the dose or amount that the organism experiences. It is thus misleading to classify or prioritize chemicals solely on the basis of their inherent toxicity, or on the basis of the concentrations in the environment or exposures. Both must be considered. A major task of this book is to estimate exposure. A healthy tension often ©2001 CRC Press LLC exists between toxicologists and chemists about the relative importance of toxicity and exposure, but fundamentally this argument is about as purposeful as squabbling over whether tea leaves or water are the more important constituents of tea. Most difficult is the issue of genotoxicity, including carcinogenicity, and terato- genicity. In recent years, a battery of tests has been developed in which organisms ranging from microorganisms to mammals are exposed to chemicals in an attempt to determine if they can influence genetic structure or cause cancer. A major difficulty is that these effects may have long latent periods, perhaps 20 to 30 years in humans. The adverse effect may be a result of a series of biochemical events in which the toxic chemical plays only one role. It is difficult to use the results of short-term laboratory experiments to deduce reliably the presence and magnitude of hazard to humans. There may be suspicions that a chemical is producing cancer in perhaps 0.1% of a large human population over a period of perhaps 30 years, an effect that is very difficult (or probably impossible) to detect in epidemiological studies. But this 0.1% translates into the premature death of 30,000 Canadians per year from such a cancer, and is cause for considerable concern. Another difficulty is that humans are voluntarily and involuntarily exposed to many toxic chemicals, including those derived from smoking, legal and illicit drugs, domestic and occupational exposure, as well as environmental exposure. Although research indicates that mul- tiple toxicants act additively when they have similar modes of action, there are cases of synergism and antagonism. Despite these difficulties, a considerable number of chemicals have been assessed as being carcinogenic, mutagenic, or teratogenic, and it is even possible to assign some degree of potency to each chemical. Such chemicals usually rank high on priority lists. As was discussed earlier, endocrine modulating substances are of more recent concern. It seems likely that ingenious toxicologists will find other subtle toxic effects in the future. 3.2.5 Long-Range Transport As lakes go, Lake Superior is fairly pristine, since there is relatively little industry on its shores. In the U.S. part of this lake is an island, Isle Royale, which is a protected park and is thus even more pristine. In this island is a lake, Siskiwit Lake, which cannot conceivably be contaminated. No responsible funding agency would waste money on the analysis of fish from that lake for substances such as PCBs. Remarkably, perceptive researchers detected substantial concentrations of PCBs. Similarly, surprisingly high concentrations have been detected in wildlife in the Arctic and Antarctic. Clearly, certain contaminants can travel long distances through the atmosphere and oceans and are deposited in remote regions. This potential for long-range transport (LRT) is of concern for several reasons. There is an ethical issue when the use of a chemical in one nation (which presumably enjoys social or economic benefit from it) results in exposure in other downwind nations that derive no benefit, only adverse effects. This transboundary pollution issue also applies to gases such as SO 2 , which can cause acidification of poorly buffered lakes at distant locations. A regulatory agency may then be in the position of having little or no control over exposures experienced by its public. The political implications are obvious. [...]... 409.8 31 9 35 4.5 38 0. 93 304 .36 290.85 290.85 37 3.4 33 0 .36 34 5.7 545.59 291.27 2 63. 5 215.68 221.04 0.0004 0.000866 0.00002 0.0005 0.008 0.0 037 4 0.0 03 0.0 53 0.001 0.000 13 0.0001 0.0006 0.002 0.00004 0.00008 221.04 214.6 2 83. 8 201.7 33 5.5 240.4 0.0045 0.00 031 0.0042 8.5x10–6 0.015 0.00 133 0.056 0.04 0.0055 0.17 60 7 .3 1 0.056 145 0.045 0.000065 12.4 25 30 400 4500 620 430 5 0.5 30 6 5.7 6.19 5.2 3. 3 3. 7 3. 81... (g/m3) Log KOW point ((C) 78.11 12700 1780 2. 13 5. 53 120.2 270 57 3. 6 – 43. 8 106.2 1270 152 3. 13 –95 120.2 450 52 3. 69 –101.6 104.14 880 30 0 3. 05 30 .6 92. 13 3800 515 2.69 –95 1 23. 11 20 1900 1.85 5.6 137 .14 17.9 651.42 2 .3 3. 85 137 .14 0.6 53 254.4 2 .37 51.7 182.14 0. 133 270 2.01 70 112.6 1580 484 2.8 –45.6 147.01 130 83 3.4 53. 1 181.45 28 21 4.1 53 215.9 4 7.8 4.5 47.5 250 .3 0.22 0.65 5 86 284.8 0.00 23. .. di-(2-ethylhexyl)-phthalate (DEHP) aldicarb aldrin carbaryl carbofuran chloropyrifos ©2001 CRC Press LLC 32 6 184 32 2 39 1 425.2 460 168.2 237 .1 30 6 4 43. 8 128.56 1 63 197.45 197.45 231 .89 266 .34 122.17 108. 13 194.2 222.26 278 .34 31 2 .39 39 0.54 0.0009 0.055 0.0000002 5.1x10–9 7.5x10–10 1.1x10–10 0 .3 0.00 039 2x10–6 5x10–10 20 12 1 1.25 0.28 0.00415 13. 02 13 0.22 0.22 0.00187 0.00115 1 .33 x10–5 190.25 36 4. 93. .. 430 0 n/a 2200 1840 32 80 n/a n/a n/a n/a n/a n/a n/a Table 3. 5 (continued) total PCB dibenzo-p-dioxin 2 ,3, 7,8-tetraCDD 1,2 ,3, 4,7,8-hexaCDD 1,2 ,3, 4,6,7,8-heptaCDD OCDD dibenzofuran 2,8-dichlorodibenzofuran 2 ,3, 7,8-tetrachlorodibenzofuran octachlorodibenzofuran 4-chlorophenol 2,4-dichlorophenol 2 ,3, 4-trichlorophenol 2,4,6-trichlorophenol 2 ,3, 4,6-tetrachlorophenol pentachlorophenol 2,4-dimethylphenol p-cresol... methoxybenzene bis(2-chloroethyl)ether bis(2-chloroisopropyl)ether 2-chloroethyl vinyl ether bis(2-chloroethoxy)methane 1-pentanol 1-hexanol benzyl alcohol cyclohexanol benzaldehyde 3- pentanone 2-heptanone cyclohexanone acetophenone ©2001 CRC Press LLC 84.94 119 .38 1 53. 82 252.75 129 .38 4 1 63. 8 98.96 167.85 202 .3 236 .74 112.99 147. 43 62.5 131 .39 165. 83 108.15 1 43. 02 171.07 106.55 1 73. 1 88.149 102.176... 100.16 106.12 86. 135 114.18 98.144 120.15 26222 26244 15250 727 19600 6670 10540 7 93 625 50 6620 492 35 4600 9900 2415 472 206 104 35 66 21.6 30 0 110 12 85 174 4700 500 620 45 132 00 8200 800 31 00 14778 4500 8606 2962 500 50 2800 1896 27 63 1100 150 2 030 10200 1700 15000 8100 22000 6000 80 38 000 30 00 34 000 430 0 230 00 5500 1.25 1.97 2.64 2 .38 1.41 2.1 1.48 2 .39 2.89 3. 93 2 2. 63 1 .38 2. 53 2.88 2.11 1.12 2.58... 221 .3 350.6 0.004 0.005 0.0000267 0.00008 0.00227 0.024 0.865 1.93x10–5 4.42x10–6 2.4x10–6 7.4x10–8 4.75 0.0145 4.19x10–4 1.16x10–6 27000 4500 500 434 1 83 14 8795 20000 4000 1080 11.2 2.69 0.285 6000 0.02 120 35 1 0. 73 6.6 4 .3 6.8 7.8 8 8.2 4 .31 5.44 6.1 8 2.4 3. 2 3. 8 3. 69 4.45 5.05 2 .35 1.96 2.12 2.47 4.72 4.68 5.11 0 1 23 305 2 73 265 32 2 86.5 184 227 258 43 44 79 69.5 70 190 26 34 .8 5 –40.5 35 35 ... 178.2 252 .3 228 .3 naphthalene phenanthrene p-xylene pyrene benzo(b)thiophene 1-methylnaphthalene biphenyl PCB-7 PCB-15 PCB-29 PCB-52 PCB-101 PCB-1 53 PCB-209 128.19 178.2 106.2 202 .3 134 .19 142.2 154.2 2 23. 1 2 23. 1 257.5 292 32 6.4 36 0.9 498.7 ©2001 CRC Press LLC 14100 4500 5100 0.0612 65.19 1.21 10620 0.11 5 0. 83 0.0208 0.001 7 x 10–7 5.7 x 10–7 10.4 0.02 1170 0.0006 26.66 8.84 1 .3 0.254 0.0048 0.0 132 0.0049... 17000 17000 550 550 170 550 1700 1700 5500 550 550 550 550 17000 55000 55000 2900 937 0 7872 2000 250 33 1 1400 1700 6400 2250 891 8000 n/a n/a 31 1.1 214.9488 0. 132 130 28 7 1.25 0.06 0.14 0. 03 0.01 0.001 10–6 3. 37 4.57 3. 18 5.18 3. 12 3. 87 3. 9 5 5 .3 5.6 6.1 6.4 6.9 8.26 80.5 101 13. 2 156 30 .85 –22 71 24.4 149 78 87 76.5 1 03 305.9 17 55 17 170 170 17 55 170 170 550 1700 1700 5500 55000 170 550 550 1700 550... (2000) Degradation Half-lives (h) Chemical Name benzene 1,2,4-trimethylbenzene ethylbenzene n-propylbenzene styrene toluene nitrobenzene 2-nitrotoluene 4-nitrotoluene 2,4-dinitrotoluene chlorobenzene 1,4-dichlorobenzene 1,2 , 3- trichlorobenzene 1,2 ,3, 4-tetrachlorobenzene pentachlorobenzene hexachlorobenzene fluorobenzene bromobenzene iodobenzene n-pentane n-hexane 1 , 3- butadiene 1,4-cyclohexadiene ©2001 . Dibenzo-p-dioxins 4,6-Dinitro-o-cresol 2 ,3, 7,8-Tetrachlorodibenzo-p-dioxin Nitrobenzene Tetrachlorinated dibenzo-p-dioxins 2,4-Dinitrotoluene Pentachlorinated dibenzo-p-dioxins 2,6-Dinitrotoluene Hexachlorinated. 2 ,3, 4,6-Tetrachlorophenol 2-Chloronaphthalene 2 ,3, 5,6-Tetrachlorophenol Polychlorinated Naphthalenes (PCNs) Pentachlorophenol 4-Chloro -3 - methylphenol Aroclor Mixtures (PCBs) 2,4-Dimethylphenol Aroclor 1016 2,6-Di-t-butyl-4-methylphenol Aroclor. 157.02 552 410 2.99 30 .8 170 1700 5500 17000 238 3 iodobenzene 204.01 130 34 0 3. 28 31 .35 170 1700 5500 17000 1749 n-pentane 72.15 68400 38 .5 3. 45 –129.7 17 550 1700 5500 90000 n-hexane 86.17 20200