Annex 1 to the Interim Report
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PersistenceInformation on the degradability is primarily based on tests examining several chlorobenzenes as a group. Half-lives of hundred up to several hundreds of days are reported for pentachlorobenzene in sediment. The ”Preliminary Risk Profile” document reaches the conclusion that the criterion for persistence in UN ECE LRTAP is met (2). This can also be supported by the presence of pentachlorobenzene in arctic samples of biota (2). BioaccumulationThe log Kow values available vary between 4.8 and 5.2 (2), indicating a high potential for bioaccumulation, borderline of meeting the criterion of the Stockholm convention. There are also studies on bioaccumulation performed that confirm a high level of bioaccumulation of pentachlorobenzene. The measured BCF values vary between 3 400 and 13 000 (2). In several cases the BCF value exceeds the limit of 5 000 in the criteria of the Stockholm Convention. ToxicityAquatic toxicity has been tested on several species representing different groups of organisms and has been shown to be very high. The lowest acute LC50 value available for freshwater organisms is 0.25 mg/l for fish and the lowest NOEC value is 0.01 mg/l for crustaceans.(1,2) In mammals, effects have been observed in different organs, e.g. liver, kidney and the thyroid gland. The EHC document refers to a subchronic dietary study where NOEL based on histopathological lesions in male and female rats is reported to be approximately 2.0 and 21.5 mg/kg bodyweight, respectively (1). The corresponding NOEL in female mice is reported to be 18.3 mg/kg bodyweight. In male mice no NOEL could be established (1). In the ”Preliminary Risk Profile” document, NOEL from a subchronic study is reported to be 12.5 mg/kg bodyweight (2). No chronic study is reported. Available tests indicate pentachlorobenzene to be teratogenic but the evidence is considered to be insufficient (1,2). The ”Preliminary Risk Profile” document concludes that pentachlorobenzene meets the criterion for toxicity in UN ECE LRTAP (2). Potential for long-range transportPentachlorobenzene is expected to degrade very slowly in air, with half-lives estimated to hundreds of days (2). Vapour pressure is 2.2 Pa at 25 ºC (2). This indicates that pentachlorobenzene possess a potential for long-range transport. This is also supported by the findings of pentachlorobenzene in arctic biota. Pentachlorobenzene is included in the list of priority substances in the field of water policy, established under Directive 2000/60/EC of the European Parliament and of the Council, establishing a framework for Community action in the field of water policy (3). In the context of the Water Framework Directive, 0.9 ng/l have been reported as the mean concentration for European surface waters based on 179 samples (83 positive samples) from 7 stations (4). In sediments 14.6 µg/kg have been reported as the mean concentration based on 459 samples (375 positive samples) from 22 stations (4). These monitoring data either indicate the substance still to be in use or to be very persistent. ConsequencesSince production and use of pentachlorobenzene probably is nonexistent or insignificant at present, the impact on society of further restrictive measures will be very small. Provided that future use is prevented and sources of emissions are identified and eliminated, levels in the environment should also decrease in the long run. The substance is a ”priority chemical” in the work of OSPAR and has been selected through the DYNAMEC-process. It is assigned to ”selection box” group E; substances with PBT properties but which are heavily regulated or withdrawn from the market. References
Polybrominated biphenyls (PBB) CAS No. 59536-65-1 and 67774-32-7 (HexaBB), 61288-13-9 (OctaBB), and 13654-09-6 (DecaBB) The group polybrominated biphenyls (PBB) contains three technical products, hexabromobiphenyl (HBB), octabromobiphenyl (OBB) och decabromobiphenyl (DBB). These products are brominated flame retardants containing 5-7, 7-9, and 9-10 bromine per molecule, respectively. The production of DBB ceased in 2000, and the production pf HBB and OBB in the 1970’s-1980’s. Thus, there is no known production of them today, but they (especially DBB) may still be present in old articles. The production of OBB never exceeded a few percent of the total production of PBBs, and is therefore not commented further below (1). Persistence The persistence of PBB is high in all media, including biota, with half-lives in the order of weeks to several years (1). Presence of HBB in different environmental samples supports that the criterion is met for HBB. Bioaccumulation The lipophilicity is very high (log Kow = 7 and 8.6 for HBB and DBB, respectively). However, the bioconcentration potential for these substances differs considerably, with BCF-values well above 5000 for HBB wheras one study on DBB indicate a BCF-value below 5 (1,2). For HBB, there are also data showing biomagnification in mink (BMF = 60), and presence in both breast milk and cow’s milk (Germany, 1988, 2 and 0.05 ng/g fat, respectively) (1). With increasing bromination, the size of the molecule increases, which probably decreases the uptake into organisms. The big size of DBB may thus explain the low potential for bioaccumulation. Wheras HBB fulfils the criterion, DBB does not. Toxicity HBB is a structural analogue to the chlorinated dioxins, and thus very toxic to most organisms, but perhaps especially to mammals after repeated exposure. Reproductive toxicity in mink and monkeys is evident at daily exposure to 1 and 0.3 mg HBB/kg feed, respectively. Other effects include developmental toxicity, immunotoxicity, toxicity to the liver, thyroid and skin, and finally weight loss and death. The NOAEL for HBB is below 1 mg/kg/day in many species. HBB is classified as a possible carcinogen (IARC group 2B) (1). DBB is less toxic than HBB, but effects on the liver has been seen after repeated exposure (NOAEL 35 mg/kg/day). Nonobromobiphenyl has caused liver tumours in experimental animals (1). It is not clear whether DBB can be considered to fulfill the criterion for adverse effects. Potential for long-range transport Low concentrations of HBB has been found in air samples from indutrial areas of the US, but there is no data on the presence in air from remote areas. The presence of HBB in marine biota may support some potential for long-range transport (Atlantic dolphins (20 ng/g fat), and seals from the Baltic (26 ng/g fat), Spitsbergen (1.9 ng/g fat) and Svalbard (0.4 ng/g fat) (1). There is no evidence for DBB fulfilling the criteria. Consequences DBB may only fulfill one of the criteria, questioning whether these conventions are the proper fora for regulation of DBB. HBB is already included in the UN/ECE LRTAP convention. One reason to incorporate HBB in the SC as well is to make sure that production will not be restarted anywhere. Since there is no known production of HBB, there would be no cost for including HBB in the SC. References
Dicofol (CAS No. 115-32-2) Dicofol is an organochlorine pesticide manufactured from DDT via DDE. The technical product consists of approximately 80% p, p’-dicofol and 20% o, p’-dicofol. Dicofol - sometimes also referred to one of its trade names “Kelhane” - is a miticidal pesticide and acaricide used on a wide variety of fruit, vegetables, ornamental and field crops. Commercial and domestic use was withdrawn in 1997 in Sweden. The summary below is mainly based upon a Dutch preliminary Risk Profile on Dicofol (1). Persistence Degradation of Dicofol in water is pH-dependent. Hydrolysis, to dichlorobenzophenones, is fast under alkalic conditions (2): the p, p’-isomer hydrolyses with a t1/2 of 85, 4 and 0.02 days at pH 5, 7 and 9, respectively. The t1/2 for the o, p’-isomer is 47, 0.3 and 0.006 days at the same pH conditions. Several field dissipation studies have been carried out with Dicofol indicating t½ in soil to be in the range 30-60 days, where the longer t½ values refer to the p, p’ isomer. No leaching from soil was observed beyond the two to three inches of the soil top layer. This confirms the results from adsorption studies in which high Koc values were determined and leaching studies in which only 0.3-1.0% of Dicofol applied was recovered in the leachate. On persistency and mobility in soil, the following is stated in the EPA RED file: “Photolysis on soil is not an important route of degradation for Dicofol, possibly due to binding on the soil and lack of solubility in soil water. o, p'-dicofol degraded with a half-life of 30 days while p, p’-dicofol degraded with a half-life of 21-30 days on silt loam soil irradiated with artificial light that does not simulate natural sunlight (MRIDs 40042036 and 40042037). The major degradates identified in the studies were the o, p' and p, p' isomers of DCBP.” Dicofol is degraded in both water and soil but the most common isomer p, p’ is more persistent than the o, p’-isomer. In water, the p, p’-isomer fulfilles the criterion t½ > 2 months only at pH 5. In soil, the t½ is slightly shorter than the stipulated 6 months. Therefore, it is uncertain if Dicofol if could meet the criteria for persistency. However the persistency in sediment is still unknown as well as the significance of cold climate on persistency in water and soil. Bioaccumulation Log KOW is reported to be in the range of 4.08 to 5.02. There are two studies of bioaccumulation in fish (Pimephales promelas and Lepomis macrochirus) that gave BCF-values at 8050 and 13500 respectively. These results are well above the criterion limit. It is therefore concluded that Dicofol does meet the criterion for bioaccumulation of 5000. Toxicity The toxicity of Dicofol has been studied in several animals. The acute toxicity in mammals is moderate with LD50 in the range 0.4-4.3 g/kg. Chronic and sub-chronic studies reveal enzyme induction and other changes in the liver, adrenal gland and urinary bladder at doses of 2.5 mg/kg. In a study, over two years, NOAEL was determined to 0.22 mg/kg and day. There are no results indicating that Dicofol should be carcinogenic in rats fed 38-47 mg/kg and day for 78 weeks. In mice, however, increased incidence of liver tumours has been reported at levels from 13.2 mg/kg and day. IARC has classified Dicofol in category 3 (Not classifiable as a human carcinogen). Studies of ecotoxicity have revealed high acute toxicity in aquatic environments. LC50 for eastern oyster has been reported to be as low as 0.015 ppm and the corresponding value for rainbow trout to be around 0.12 ppm. Dicofol has been shown to affect eggshell quality and a NOEC at 2.5 ppm in feed has been established, while hatchability was affected at 40 ppm. In falcons, feminised embryos from females given 5 mg/kg have been reported. Dicofol is moderately toxic to mammals and not carcinogenic. In wildlife it is reported to be reprotoxic. In birds, Dicofol may reduce the eggshell quality. Based on the acute toxicity tests, Dicofol is very toxic to the aquatic environment. Potential for long-range transportThe vapour pressure of Dicofol is low, being less than 5,3x10-5 Pa. The calculated t½ in air is 3.1 days. No experimental data are available. Based on the vapour pressure, Dicofol is expected to partition between the gas and particle phases in the atmosphere and is likely to exist largely in the particle phase. The average half-life time for particles is estimated to be about 3,5 – 10 days and the average lifetime for particles is estimated to be about 5 - 15 days. Analyses of Dicofol in connection to sites with high use indicate that the loss is small from these areas. There is however one study where Dicofol has been analysed in water and sediment down-stream an application site. In the water the levels were too low to be detected but in sediment Dicofol was found at levels ranging from 6.8 to 23.7 ng/L. There is no information on analyses of Dicofol from Arctic regions. The California Air Toxics Program has published a Toxic Air Contaminant Fact Sheet on Dicofol where it is stated: “In 1970 787 samples were taken from 14 states and Dicofol was not detected. In 1971 667 samples taken from 16 states showed 0.15 percent positive results for Dicofol, with an average concentration of 9.5 ng/m3. In 1972 1025 samples were taken from 16 states and Dicofol was not detected”. Based on vapour pressure and an atmospheric half-life of >2 days, Dicofol meets the criteria for long-range atmospheric transport
Dicofol is listed in the Commission Regulation 1490/2002 laying down the detailed rules for the third stage of EU review program of active substances in plant protection products, which means that Dicofol will be assessed within the next few years. References
Endosulfan (1,4,5,6,7,7-hexachloro-8,9,10-trinorborn-5-en-2,3-ylenbismethylene) sulfite. CAS No.: 959-98-8 (-isomer), 33213-65-9 (-isomer), 115-29-7 (technical material, consisting of a 2:1 mixture of the - and -isomer). Both isomers are biologically active. The CAS No. for one of the breakdown products of environmental importance, endosulfan sulfate, is 1031-07-8.
12 000-13 000 tonnes in the mid-1990's (1). Consumption within western Europe (EU plus Switzerland) was reported to 840-1 030 tonnes per year during 1994-1996, to 470-590 tonnes in 1997-1999, reflecting a reduction in use, mainly in the northern countries (1). In Sweden, pesticides containing endosulfan as active ingredient were registered until 1995. Directory: fileadmin -> DAM -> env DAM -> United Nations st/SG/AC. 10/C. 3/2016/42 DAM -> United nations e DAM -> United Nations ece/trans/2016/33 DAM -> United Nations ece/trans/WP. 15/AC. 1/2014/13 DAM -> Technical Report on the development of a World-wide Worldwide harmonised Light duty driving Test Procedure (wltp) DAM -> WP. 29-153-32 (153rd wp. 29, 8-11 March 2011, agenda item 8) Korea Motor Vehicle Safety Standards Enactment/Revision Procedure for Automobile Management Act and Self Certification System DAM -> United nations e Download 172.3 Kb. Share with your friends:
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