The addition of humic acid to cultures of rainbow trout was shown to reduce the toxicity of cationic polymers up to 75-fold depending upon the concentration of the humic acid in the cultures. The concentrations of PFOS and PFOA are significantly higher in maternal serum (4.9–18.1 and 0.5–2.6 μg/L, respectively) than in umbilical cord serum (1.6–7.3 and 1.6–3.4 μg/L, respectively) (Inoue et al., 2004; Apelberg et al., 2007a; Midasch et al., 2007; Monroy et al., 2008), but in umbilical cord serum the difference between PFOS and PFOA concentrations is not as pronounced, which means that PFOA, but not PFOS, crosses the placental barrier obviously unhindered (Midasch et al., 2007). The microcosms were flow-through systems with natural river water and clean sediment. Daphnid 48 h EC50 values (based on immobilization) ranged from 126 to >1200 mg l−1. The following discusses telomer environmental toxicity. The similar potency was found for the synthetic analog of glycyrrhetinic acid, carbenoxolone (Chen et al., 2009; Ge et al., 1997). From: International Encyclopedia of Public Health, 2008, P. de Voogt, in Encyclopedia of Toxicology (Third Edition), 2014. Perfluorooctanesulfonic acid, PFOS, and perfluorooctanoic acid, PFOA, are synthetic fluorinated organic compounds used in many industrial and consumer products such as nonstick cookware, stain-resistant fabric and carpet and some food packaging. Consultation with a poison control center is recommended for serious acute poisoning exposures. An environmental risk assessment case study has been conducted for a C12–C18 monoalkyl quaternary ammonium compound (MAQ). ���� JFIF ,, ��� Chronic toxicology studies have indicated that although both PFOS and PFOA may induce adenomas, neither compound is genotoxic (EFSA, 2008), suggesting that a threshold dose must be met before adenoma formation. The licorice-caused apparent mineralocorticoid-like syndrome was first observed in 1953 (Borst, Ten Holt, De Vries, & Molhuysen, 1953). �� ,Photoshop 3.0 8BIM% ��ُ �� ���B~�� C �� C�� l �" �� Measured chronic NOEC and LOEC values in four different surface water tests ranged from 0.05 to 0.10 mg l− 1 MAQ (NOEC and LOEC in laboratory water ranged from 0.01 to 0.04 mg l− 1). Contaminated food and drinking water could be the dominant human exposure pathway for PFOS and PFOA, but the lack of data makes it difficult to determine this (Tittlemier et al. Their remarkable chemical stabilities, hydrophobic and lipophobic properties, and thermal stabilities (Buck et al., 2011) provide excellent physiochemical platforms that are adaptable to a diverse number of commercial and industrial applications. Perfluorooctanoic acid (PFOA) (conjugate base perfluorooctanoate), also known as C8, is a synthetic perfluorinated carboxylic acid and fluorosurfactant. Natural phytoplankton and zooplankton structural and functional parameters were assessed as well as biodegradation rates. %PDF-1.4 Acute and chronic toxicity tests were conducted with MAQ in river and lake waters. Perfluorooctanoic acid (PFOA), also known as C8, is an artificial acid that has many industrial uses. NOEC values ranged from 12.5 to 430 mg l− 1. 2008). For example, the plasmas half-life of PFOA in beef cattle is approximately 19 ± 3 hours (Lupton et al., 2012), whereas in humans, its serum half-life is estimated to be 3.8 years with a 95% CI of 3.1–4.4 years (Olsen et al., 2005b as cited by EFSA, 2008). Both the acute LC50 values and the chronic LOEC levels averaged threefold higher in natural surface water for daphnids, the most sensitive species. Collectively, animal and human data suggest that PFOA be categorized as “known to be toxic” with respect to human reproduction and development (Lam et al., 2014). Nevertheless, PFOA and PFOS are still produced in China and other developing Asian countries in large quantities. Indigenous fish, macroinvertebrates, and periphyton were much less sensitive to MAQ than was the most sensitive laboratory species D. magna. 2009; D’Hollander et al. ����F��8��������� u� �#����ߍ�� �?���� DG_9W���"� �u�� TABLE 47.2. Cationic polymers contain a positive charge density. A trend suggesting decreases in toxicity with increasing molecular weight was noted. h��U�O[U?���}��}���ŔǗ�Y(h��]�����a��48#�L�>�3o�.�1��e)��%�����:#K$�1j��&���Q�}�������s�=��9祽 @�~ s���Ѓ?��L'Ļ�@�`� ��B��u��>���F���0��g���}��iJ����nv��1�l�5�&a��?��8�H/�oZ�=����R9�L�rd��B�Y�OZ���9��^LU7�y¯gn�fj�'}7jUUB�W�����cU]u>���tځ����$�a�Y�3�hM�&�'�o������W�˝�� ���f�c�b� ��b8�3e�½����۩�7���������-m�*���Y�� ��E����r7�}��*r�]���46�0�&*_�&rowo}g�m���?��,(,��5Q�;v�4[6��)Ez�)�� �8G_"7[��,��Fѷ���^O�c4�=_�^��;3�^��Ə��Jﶷe~���q��u��-��ƪAα��vЉo�M��E'/�����l��������j��o��o�̌�v{�ĸf�_r��L3�v*3��p1�0]��b�}��9�T�aN�֝:z�!�E> ����g !�y_�%�:��lC�%wqy$�o�I��"I�y�}h���K�Rb����3��X���KJ�D��yw՗4�r�x�I�D�{�m���LX�Ж�^��^�L�X��d M��X���x���R�Uއ1:0i�6όx6ƾ"��n0�G�7�?P������m��-���?�O��@�h DX���K�-��&���8p��p>4͢�GqzX�;D�L�o�`E9ND���&QP��d!F@N�D�$� C�,&Ƀ]���ԄB�~5�\3��Β��D&Q���,�"��&�Ԧ&[�PTJE`#�2�4�JPbϴ�O&�(�H�O`�[ӡ��I�#*e�INd�̽>Q�d���J��r��w����&A�'r$O3�`���O���ks�Ot�o����$�t��L������CxQG�c]�,�N����5�ɤ�s@�| �e���K��EL��-� ��!� Water-soluble charged polymers are classified according to their charge potential as cationic, anionic, nonionic, and amphoteric. WAF fortifications in the form of iron or disodium ethylenediaminetetraacetic acid (EDTA) ranging from 200% to 1000% of the standard algal medium concentration mitigated any toxicity noted in unamended cultures. In December 2002, following a large-scale pollution, 3M Co. stopped making PFOA perfluorooctanoic acid (C 8 HF 15 O 2) and perfluorooctane sulfonyl PFOS (C 8 HF 17 O 3 S) that they produced at the plant in Cottage Grove, Minnesota. Median concentrations of PFOA in muscle and liver of over 500 hogs (Stahl et al., 2012) were below the limits of quantitation (LOQs; 1 and 5 μg/kg, respectively); median PFOS concentrations in livers, however, were 49 μg/kg and not detectable in muscle (LOQ 1 μg/kg). Thus, hormonal fluctuations induced by chronic exposures to PFOA have limited, moderate-term consequences on fish reproductive capacity. Under environmentally relevant conditions in aqueous environmental compartments, PFOA will exist as the fully ionized component (COO−). Paratanytarsus parthenogeneticus LC50 values were less than 100 mg l− 1 for three of the eight cationic polymers tested (< 6.25 to 50 mg l− 1). Leping Ye, ... Ren-Shan Ge, in Vitamins & Hormones, 2014. For PFOA, the majority of the aquatic ecotoxicity studies have been conducted with the ammonium salt (APFO) of the prefluorooctanoic acid. For PFOA, the majority of the aquatic ecotoxicity studies have been conducted with the ammonium salt (APFO) of the prefluorooctanoic acid. The contributions of dietary exposure to PFOS and PFOA are reported as 91% and 99%, respectively, of the total intake in the general population (Fromme et al. That is, estimated oral LD50 values in rats for PFOS is 0.25 g/kg b.w. Populations acclimated to lower concentrations and subsequently exposed to 0.180 mg l− 1 were not adversely affected. Although carbenoxolone can produce apparent mineralocorticoid-like syndrome, the exact mechanism was not understood until the cloning of 11β-HSD2 in 1995. Table 7 suggests that fish are more sensitive to PFOS than invertebrates or algae based on subchronic or chronic exposures. The UK Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) recommended a maximum TDI of 300 ng/kg body weight and 3000 ng/kg body weight for PFOS and PFOA, respectively (COT 2006a; 2006b).