Species Susceptibility

Examples of differences in the responses of wildlife organisms to EDCs include the differences in sensitivity to phthalates and bisphenols among mollusks, crustaceans, and amphibians compared to fish. In invertebrates, biological effects are observed at exposures in the ng/L to low pg/L range, compared to high pg/L for most effects in fish (reviewed in Oehtmann et al. 2008). In addition, aquatic mollusks tend to bioconcentrate and bioaccumulate pollutants to a greater level than hsh, possibly owing to poorer capabilities for metabolic detoxification (see Chapter 4, Section 4.3). 

Organic Pollutants An Ecotoxicological Perspective, Second Edition 

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Hepatic peroxisome proliferation, characterized by liver enlargement due to hyperplasia and hypertrophy, has been proposed as a basis for differences in species susceptibility to trichloroethylene carcinogenicity. Peroxisomes are membrane-bound organelles which contain enzymes generally involved in lipid metabolism. 

Changes in bulk reactant concentration during the limiting current measurement, due, for example, to variations in gas pressure (oxygen reduction) or to the presence of other species susceptible to reduction at the... 

Protonated N-hydroxy arylamines have also been proposed to be ultimate carcinogens for the urinary bladder (16,17,140,141) since urine pH is slightly acidic in a number of species (14,142). Furthermore, pharmacokinetic studies have shown that increased urine acidity and decreased frequency of urination are predictive of relative species susceptibility to urinary bladder carcinogenesis (142) and neoplastic transformation of cultured human fibroblasts by N-hydroxy arylamines is greatly enhanced by incubation at pH 5 as compared to pH 7 (143). 

Because the respiratory tracts of humans and monkeys are more similar than those of humans and rodents, because uptake is more rapid in the monkey than in humans, and because both species have been shown to be relatively insensitive to the incapacitative and lethal effects of HCN (but at the same time, species susceptibilities to lethal effects do not differ by more than a factor of 1.5), an interspecies UF of 2 was applied. Human (adult) accidental and occupational exposures (El Ghawabi et al. 1975) indicate that there are individual differences in sensitivity to HCN, as evidenced by symptoms fol... 

Marked differences in species susceptibility to 7 -DNB have also been observed." Hamsters showed no testicular lesions at dose levels up to 50mg/kg, whereas damage to rat testicular tubules was readily apparent at 25mg/kg. Similarly, -DNB induced substantially less methemoglobin in the hamster than in the rat (15% vs. 80% at 25 mg/kg dose). 

Whittaker (4), Waller and Nowacki (5.), and Rabotnov (6) discussed the evolution of stable plant communities and species susceptible to allelopathic chemicals that were released by other plants. Such plants would have been eliminated by natural selection, and allelopathically neutral or allelopathically... 

An experimental attempt towards polycatenanes 9, based on a strategy related to the stepwise polycondensation approach, was reported in the seventies. Karagoumis et al. took advantage of the interface between a nonpolar phase (air, CC14) and a polar phase (H2O, Hg) to orient alkanes a,oj-disubstituted with polar groups (Scheme 9) [45], The successive addition of macrocycles of ring sizes 15-60 atoms and of difunctional species, susceptible to reaction with the a,o>disubstituted al-... 

The thiolate anion (RS ) is the species susceptible to reaction with oxygen. 

The compound may react as a typical metal(0) species, susceptible to substitution and oxidative addition reactions. Both are promoted by the unsaturated nature of the molecule, which is the first stable four-coordinate iron(0) species to be observed at ambient temperature. 

Many other phytotoxins not presented here have been structurally characterized and tested In some plant bioassay systems. Numerous other reported phytotoxin studies are In the "active fraction" stage and structure elucidation of the active components has not been achieved. Nevertheless, from the data presented. It can generally be concluded that diverse microbes produce a broad range of chemistries with phytotoxic activities chemical and biochemical synthesis of almost all of these compounds Is unknown (but derivitizatlon studies to alter phytotoxic activity have been used In a few Instances) knowledge of the spectrum of species susceptible to these compounds Is Incomplete (many weed and crop species have not been tested some compounds are toxic to organisms other than plants) and the molecular mode of phytotoxin action Is unstudied or unknown for most. The major exception Is the vast amount of data on blalaphos, phosalacine, and phosphinothricin, which have achieved commercial status. 

On the basis of the available data, the rabbit appears to be unusually susceptible to the lethal effects of uranium s metallotoxicity. The order of animal species susceptibility to acute uranium toxicity has been suggested as follows rabbit > rat > guinea pig > pig > mouse (Orcutt 1949). 

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