Acute and Chronic Effects of Perfluorobutane Sulfonate (PFBS) on the Mallard and Northern Bobwhite Quail

Perfluorobutane sulfonate (PFBS) can be a final degradation product of perfluorobutane sulfonyl fluoride (PBSF)-based chemicals. Surfactants based on this chemistry are potential replacements for perfluorooctane sulfonate (PFOS)-related products and have many potential applications in industrial and commercial processes and applications. To evaluate the potential hazard that PFBS may pose to avian species, acute dietary studies with juvenile mallards and northern bobwhite quail, as well as a quail dietary chronic study of reproduction were conducted. In the acute studies, 10-day-old mallards and quail were exposed to nominal dietary concentrations of 1,000, 1,780, 3,160, 5,620 or 10,000 mg PFBS/kg feed, wet weight (ww) for 5 days and the birds were then fed an untreated diet and observed for up to 17 days. No treatment-related mortalities were observed in the study up to 10,000 mg PFBS/kg, ww feed. Body weight gains of quail exposed to 5620 or 10,000 mg PFBS/kg feed were statistically less than that of unexposed controls. Weight gain of mallards exposed to 10,000 mg PFBS/kg feed was statistically less than that of controls. There were no statistically significant effects on feed consumption of either species. In the acute studies, no observed adverse effect concentration (NOAEC) for mallards and quail were 5620 and 3160 mg PFBS/kg, ww feed, respectively. In a reproduction study, adult quail were exposed to nominal dietary concentrations of 100, 300, or 900 mg PFBS/kg, ww feed for up to 21 weeks. There were no treatment-related mortalities or effects on body weight, weight gain, feed consumption, histopathology measures, or reproductive parameters evaluated in the study when compared to the control group. Concentrations of PFBS in blood serum, liver, and eggs were dose-dependent but were less than the administered dose, indicating biodiminution. Based on the results from the quail reproduction study, the dietary NOAEC was 900 mg PFBS/kg, ww feed (equivalent to an ADI of 87.8 mg PFBS/kg bw/d).     

Mallard reproductive testing in a pond environment: A preliminary study

A 2-year preliminary study was conducted on mallard ducks (Anas platyrhynchos), to determine the feasibility of using outdoor pond enclosures for reproductive studies and to evaluate the effects of the insecticide chlorpyrifos on mallard reproduction. No significant reproductive effects were observed for mallards receiving 8 ppm (mg/kg of feed) chlorpyrifos in their diet. Birds receiving 80 ppm chlorpyrifos hatched significantly (p < 0.05) fewer ducklings per successful nest (5.8) than controls (10.2). None of the ducklings on treatment ponds survived to 7 days. Control birds produced 8.4 ducklings per successful nest surviving to 7 days or longer. Birds in the 80 ppm treatment group consumed less feed than did controls (p < 0.01). Weight loss from reduced feed consumption did not occur to the extent expected, indicating that birds supplemented their diets with natural foods found in and around the ponds. In spite of relatively low treated feed consumption, brain acetylcholinesterase was significantly (p < 0.05) depressed (57% of controls) for 80 ppm treated birds. Studies on indoor penned mallards fed 80 ppm chlorpyrifos in their diet also resulted in acetylcholinesterase depression to the same extent, but at much higher feed consumption levels. The study demonstrated the potential of using outdoor pond enclosures to evaluate chemical effects on food consumption, brain acetylcholinesterase, and reproduction in mallards. Improvements to the study design and to the pond enclosures are discussed.     

Studies on combined effects of organophosphates and heavy metals in birds. I. Plasma and brain cholinesterase in coturnix quail fed methyl mercury and orally dosed with parathion

Summary We found that mercury potentiated the toxicity and biochemical effects of parathion. Male Coturnix quail (Coturnix coturnix japonica) were fed a sublethal concentration of morsodren (4 ppm as methyl mercury) for 18 weeks. This resulted in an accumulation of 21.0 ppm of mercury in the liver and 8.4 ppm in the carcass. Birds fed clean feed and those fed morsodren-treated feed were orally dosed with 2, 4, 6, 8, and 10 mg/kg parathion, and their 48-h survival times compared. The computed LD₅₀ was 5.86 mg/kg in birds not fed morsodren and 4.24 in those fed the heavy metal. When challenged with a sublethal, oral dose of parathion (1.0 mg/kg), morsodren-fed birds exhibited significantly greater inhibition of plasma and brain cholinesterase activity than controls dosed with parathion. Brain cholinesterase activity was inhibited 41% in morsodren-fed birds and 26% in clean-fed birds dosed with parathion, which suggested that the increase in parathion toxicity in the presence of morsodren was directly related to the inhibition of brain cholinesterase.     

Transfer of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) From Contaminated Feed Into Milk and Meat of Sheep: Pilot Study

A pilot study was performed with dairy sheep to generate the first data on the transfer of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from feed into food of animal origin. Corn silage was cultivated on cropland in Lower Saxony in Germany where, as a result of illegal waste disposal in 2006, farmland was contaminated with perfluorinated alkylacids (PFAAs). Two sheep were exposed by way of PFAA-contaminated corn silage to PFOS (1.16 and 1.45 μg/kg body weight [bw]/d, respectively) and PFOA (0.43 and 0.53 μg/kg bw/d) during a period of 21 days. During the PFAA-feeding period, PFOS levels in plasma increased continuously to maximum concentration of 103 and 240 μg/L for sheep 1 and sheep 2, respectively. The PFOA plasma concentration remained low (sheep 1 = 3.3 ± 2.2 μg/L; sheep 2 = 15.6 ± 8.3 μg/L). Data indicate that urinary excretion is the primary clearance route for PFOA (sheep 1 = 51 %; sheep 2 = 55 %), whereas PFOS excretion by way of urine could not be quantified. The highest PFOS excretion (4 to 5 %) was detected in faeces. PFOS was also excreted at higher levels than PFOA by way of milk. During a period of 21 days, a total PFOS transfer into milk ≤ 2 % was calculated. Overall, total excretion of PFOS was significantly lower compared with that of PFOA (PFOS 6 %; PFOA 53 to 56 %). PFOS levels in sheep 1 and sheep 2 were highest in liver (885 and 1,172 μg/kg weight wet [ww], respectively) and lowest in muscle tissue (24.4 and 35.1 μg/kg ww, respectively). PFOA levels in muscle tissue were low for sheep 2 (0.23 μg/kg ww) and not detectable after the PFAA-free feeding period in sheep 1. A slight background load of PFOS in liver (1.5 μg/kg ww) and kidney (0.3 μg/kg ww) was detected in sheep 3 (control).     

Magnesium proteinate is more protective than magnesium oxide in heat-stressed quail

We evaluated the effects of dietary supplementation with Mg-oxide and Mg-proteinate on performance; nutrient digestibilities; malondialdehyde (MDA) concentrations in serum, liver, and thigh meat; and serum cholesterol and triacylglycerol concentrations in Japanese quail (Coturnix coturnix japonica) exposed to high ambient temperature. The birds (n = 360; 10 d old) were randomly assigned to 12 treatment groups consisting of 6 replicates of 5 birds each in a 2 x 2 x 3 factorial arrangement (temperature, Mg source, Mg level). Birds were maintained in temperature-controlled rooms at 22 degrees C for 24 h/d or 34 degrees C for 8 h/d (0900-1700 h) and fed a basal diet or that diet supplemented with 1 or 2 g Mg-oxide or Mg-proteinate/kg of diet. Heat exposure decreased (P = 0.0001) live weight gain, feed intake, feed efficiency, and carcass weight in quail fed the basal diet. A linear increase in feed intake (P = 0.008) and body weight (P = 0.001), and improvements in feed efficiency (P = 0.001), carcass weight (P < 0.0001), digestibility of dry matter, organic matter, crude protein, and ether extract were found in Mg-supplemented, heat-stressed quail. The effects of Mg-proteinate were greater than those of Mg-oxide (P < or = 0.0001). Serum Mg (P = 0.001) concentration increased, whereas the concentration of MDA in serum (P = 0.0001), liver (P = 0.04), and thigh meat (P = 0.0001) and serum triglyceride and cholesterol concentrations decreased linearly (P = 0.001) with the level of Mg in the diet. Interactions between dietary Mg source, temperature, and level of supplementation (P < or = 0.05) were found for several variables. Results of the present study suggest that supplementation with Mg-proteinate is more protective than Mg-oxide in reducing the negative effects of heat stress in quail.     

Acute Toxicity and Sublethal Effects of White Phosphorus in Mute Swans, Cygnus olor

Among the waterfowl affected by white phosphorus (P₄) at a military base in Alaska are tundra (Cygnus columbianus) and trumpeter (C. buccinator) swans. To estimate the toxicity of P₄ to swans and compare the toxic effects to those of mallards (Anas platyrhynchos), we dosed 30 juvenile mute swans (C. olor) with 0 to 5.28 mg P₄/kg body weight. The calculated LD₅₀ was 3.65 mg/kg (95% CI: 1.40 to 4.68 mg/kg). However, many of the swans still had P₄ in their gizzards after dying, as determined by “smoking gizzards” and characteristic odor, and a lower LD₅₀ might be calculated if all of the P₄ had passed into the small intestines. We attribute the retention of P₄ in swans to the possibility that P₄ pellets were mistaken for the similarly sized grit in their gizzards. Most swans took 1 to 4.5 days to die in contrast to the few hours normally required in mallards and death appeared to be related more to liver dysfunction than to hemolysis. White phosphorus affected several plasma constituents, most notably elevated aspartate aminotransferase, blood urea nitrogen, lactate dehydrogenase, and alanine aminotransferase. Received: 15 May 1998/Accepted: 7 October 1998     

植物甾醇酯对实验大鼠血脂水平的影响

目的探讨植物固醇酯(PSE)对大鼠血脂水平的影响。方法(1)在高脂饲料喂养模型下,4组大鼠分别给予不含(模型组)或含有3个剂量PSE(分别为4·0、16·0、32·0mg/kgbw)的油溶液,30天后测定血脂水平。(2)摘除卵巢的去势大鼠分为模型组,E2组(22·5μg/kgbw己烯雌酚),PSE组(32·0mg/kgbwPSE)和FPE组(500mg/kgbw游离型植物固醇),60天后测定血脂、雌激素,及大鼠子宫、肝脏重量。各实验均设正常对照组以确认造模成功。结果PSE使高脂饲料喂养大鼠甘油三酯(TG)水平下降,高剂量PSE组大鼠总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)明显降低,高密度脂蛋白胆固醇(HDL-C)及HDL-C/TC升高(P<0·05)。去势模型使大鼠体重、肝脏重量、TC、TG和LDL-C明显升高,雌激素水平和子宫重量显著下降(和对照组比,P<0·05)。PSE和FPS可显著降低去势大鼠体重和肝重,使TC和TG水平下降,子宫重量略有增加(P<0·05),但作用未及E2(P<0·05),对雌激素水平也没有显著影响。结论植物固醇酯具有明显降血脂作用。     

Estimated daily intake of benzoic acid through food additives in adult population of South East Serbia

The aim of this study is to estimate dietary intake of benzoic acid and its salts through food additives in adult population of South East Serbia. Information on dietary intake among 620 adults (aged 18-65) was collected using a food frequency questionnaire, and 748 food samples were analyzed. The mean estimated intake of benzoic acid -0.32 mg/kg of body weight (bw) per day was below acceptable daily intake (ADI). Dietary exposure to benzoic acid (0.36 mg/kg of bw/day; 7.2% ADI) (consumer only), also did not exceed ADI. The main contributors of benzoic acid to dietary intake were non alcoholic beverages (43.1%), ketchup and tomato products (36.1%), and domestic pickled vegetables (19.4%). The results of this study indicate that dietary exposure to benzoic acid and its salts through food preservatives does not represent a public health risk for the adult population of South East Serbia.     

孕期母鼠接触三丁基氯化锡对子代雌性大鼠发育和性激素的影响

目的 通过对母鼠进行孕期染毒来检测三丁基氯化锡(TBTC)对子代雌性大鼠的发育毒性和性成熟后生殖系统的影响.方法 选择SPF级3月龄的健康成年Wistar大鼠,按雌:雄为2:1比例同笼配种.取妊娠大鼠16只,随机分为4组(1个对照组和3个处理组),于妊娠第12～20天,将对照、低、中、高剂量组分别按0、1.0、2.5、5.0mg/(kg·d)进行灌胃染毒.将出生后第70天的子代雌性大鼠称重后断头处死,称量肝脏、肾脏、子宫、卵巢的重量,计算脏器系数并做病理切片.采用放射免疫法测量血清中促卵泡激素(FSH)、促黄体生成激素(LH)、睾酮(T)、雌二醇(E2)的含量.结果 高、中剂量组体重的增长速度低于对照组,差异均有统计学意义(P＜0.05).高、中剂量组肾脏重量分别低于对照组,高剂量组卵巢重量低于对照组,差异均有统计学意义(P＜0.05).且肝脏、肾脏重量随着染毒剂量的升高而降低.各剂量组肝脏、肾脏、子宫、卵巢的脏器系数间比较,差异均无统计学意义(P＞0.05).高剂量组FSH、E2水平均高于对照组,差异有统计学意义(P＜0.05).各剂量组血清中均未检测出T.各剂量组肝脏、肾脏、子宫、卵巢的组织切片均未见明显的病理学改变.结论 孕期母鼠接触TBTC,可抑制子代雌性大鼠的生长发育,并可引起FSH及E2水平的升高.     

Biochemical Responses and Accumulation Properties of Long-Chain Perfluorinated Compounds (PFOS/PFDA/PFOA) in Juvenile Chickens (<Emphasis Type="Italic">Gallus gallus</Emphasis>)

One-day-old male chickens were exposed via oral gavage to mixtures of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and perfluorodecanoate (PFDA) at either a low dose (0.1 mg/kg body weight [b.w.]) or a high dose (1.0 mg/kg b.w.), or a saline/ethanol vehicle control, three times a week for 3 weeks. After 3 weeks of exposure, half of the chicks were sacrificed and the other half were allowed to depurate for a further 3 weeks. No dose-dependent statistically significant differences in body/organ weights were observed among treatment and control groups after 3 weeks of exposure or after three 3 of depuration. Neither 15 histological nor 14 measured plasma biochemical parameters were significantly different in chicks from the exposed groups and vehicle controls. PFOS, PFDA, and PFOA concentrations in blood/liver/kidney samples were measured throughout the exposure and depuration periods at different time intervals. PFOS and PFDA accumulated at much higher concentrations than PFOA during the experimental periods. Interestingly, PFOS and PFDA accumulation patterns in the blood were similar during the exposure and depuration periods. The half-lives for each PFC at the 0.1 and 1.0 mg/kg doses were, respectively, approximately 15 and 17 days for PFOS, 11 and 16 days for PFDA, and 3.9 and 3.9 days for PFOA. PFDA accumulation in organs was greater than or similar to that of PFOS: the liver was the main target during exposure and the blood was the main reservoir during depuration. These results indicate that exposure to a 1.0-mg mixture of PFOS/PFDA/PFOA/kg b.w. has no adverse effect on juvenile chickens.     

Subchronic effects of sodium selenite and selenomethionine on several immune-functions in mallards

The subchronic effects of selenomethionine (SeM) and sodium selenite (SeL) on several immunologic, hematologic, and serologic parameters in mallards were measured, using concentrations in drinking water of 0, 0.5, and 3.5 mg/L selenium (Se) as SeL and 2.2 mg/L (Se) as SeM. Cyclophosphamide (CP) was used as an immunosuppressive control at 20 mg/L. A battery ofin vivo andin vitro immunologic assays was performed on each bird throughout the 12 week study. The SeM-treated birds displayed a significantly impaired delayed-type hypersensitive (DTH) response to tuberculin (M. bovis), as measured by the number of positive reactions present 24 hours post PPD challenge (p 0.05). The SeM-treated group also exhibited a significantly increased serum alanine aminotransferase (ALT) activity and an increased plasma glutathione peroxidase (GPX) activity (p 0.05). Selenium concentration in the liver and breast muscle of SeM-treated birds was significantly elevated 4- and 14-fold, respectively, over controls (p < 0.05). Body weight and water consumption of treated birds did not differ from controls. Organ weights were not significantly affected by any Se treatment. Sodium selenite-treated birds displayed no detectable differences in immune-function or Se accumulation in tissues as compared to controls. Serum ALT activity was significantly increased in the 3.5 mg/L group, although to a lesser extent than in SeM-treated birds. Cyclophosphamide significantly depressed white blood cell number, testes weights, and also suppressed the DTH reaction. Concentrations of Se as SeL did not affect the immune system, whereas low concentrations of SeM (2.2 mg/L Se) appeared to suppress certain aspects of the mallard immune response.     

Aluminum and Acid Effects on Calcium and Phosphorus Metabolism in Young Growing Chickens (Gallus gallus domesticus) and Mallard Ducks (Anas platyrhynchos)

Acidification is associated with increased mortality, reduced growth, and bone abnormalities in birds. Associated with acid deposition is an increase in aluminum availability due to solubilization from soil and other sources. (Conversely, experimental diets containing aluminum sulfate have much reduced pHs.) The present studies compare the effects of two levels of dietary acid (sulfuric acid) (0.122 and 0.56 mol H⁺ per kg feed; 0.056 and 0.277 mol sulfate per kg feed) and dietary aluminum (aluminum sulfate at 0.1 and 0.5%; sulfate at 0.056 and 0.277 mol sulfate per kg feed) on bone growth, mineralization, and phosphorous/calcium homeostasis in growing birds (chickens and mallard ducks). Growth was reduced by the high acid (chicken) and aluminum (ducks and chickens) diets. A reduction in bone mineralization was observed in birds receiving aluminum-containing diets [low aluminum diet: decreased tibia ash, calcium, and phosphorus (chickens); high aluminum diet: decreased tibia dry weight, % of ash and mg; ash, calcium (chickens, ducks as % of ash), and phosphorus (chickens mg/duck, % of ash)]. Moreover, plasma concentrations of inorganic phosphate were reduced in chicks on the high aluminum diet. There were also marked decreases in bone growth and mineralization [tibia weight, ash (mg), calcium (mg), phosphorus (mg)] and plasma concentrations of 1,25-dihydroxy vitamin D₃ in chicks on the high acid diet compared to those on a control diet. These changes were probably due to reduced feed intake; changes in bone indices being of a greater or similar magnitude in pairfed control. There was little change in bone indices, growth rate or feed consumption in ducklings receiving either the low or high acid diets. It is concluded that aluminum directly adversely affected bone mineralization whereas acid effects are mediated in part by changes in feed consumption. Received: 22 July 1997/Accepted: 29 November 1997     

Chromium supplementation can alleviate negative effects of heat stress on egg production,egg quality and some serum metabolites of laying Japanese quail

This study was conducted to determine the effects of Cr (chromium picolinate, CrPic) supplementation at various levels (0, 200, 400, 800 or 1200 microg/kg of diet) on egg production, egg quality and serum concentrations of insulin, corticosterone and glucose in laying Japanese quail (Coturnix coturnix japanica) reared under conditions of heat stress (32.5 degrees C). Laying Japanese quail (n = 150; 45 d old) were divided into five groups of 30 birds. The quail were fed either a control diet containing 965 microg Cr/kg diet or the control diet supplemented with 200, 400, 800 or 1200 microg of Cr/kg diet. Increased supplemental chromium increased body weight (P = 0.05, linear), feed intake (P = 0.05, linear), egg production (P = 0.01, linear) and also improved feed efficiency (P = 0.01, linear). Increased supplemental chromium linearly increased egg weight (P = 0.01), eggshell thickness, egg specific gravity (P = 0.05) and Haugh unit (P = 0.01). Serum insulin concentration increased linearly (P = 0.01), whereas corticosterone and glucose concentration decreased linearly (P = 0.05) as dietary chromium increased. The best results were obtained with 1200 microg Cr/kg diet, and chromium supplementation at such a level can be considered to be protective management practice in a quail diet, reducing the negative effects of heat stress.     

大豆异黄酮对膳食诱导胰岛素抵抗大鼠脂联素基因表达的影响

目的探讨大豆异黄酮(SIF)改善高脂高糖膳食诱导大鼠胰岛素抵抗(IR)状态的作用及可能机制。方法选用高脂高糖饲料诱导的IR雄性SD大鼠,根据胰岛素抵抗指数(IRI)随机分为模型对照组和3个SIF剂量组(50、150及450mgkgbw)。各组给予相应受试物1月后,试纸法检测各组大鼠血糖、放免法检测血胰岛素、酶免法检测血脂联素含量,实时定量RTPCR法检测肾周脂肪组织脂联素基因的mRNA水平。结果与模型对照组比较,450mgkgbw组能明显降低大鼠体重及内脏脂肪含量、提高脂肪组织脂联素基因mRNA的表达、促进脂联素的分泌。150mgkgbw和450mgkgbw组能显著降低血胰岛素水平及IRI。3个SIF剂量组的血糖与模型对照组比较无明显差异。IRI与血清脂联素水平存在着明显的负相关。结论SIF具有减少大鼠脂肪沉积、促进脂联素的分泌、提高胰岛素敏感性的作用。     

Strychnine Alkaloid and Avian Reproduction: Effects Occur at Lower Dietary Concentrations with Mallard Ducks Than with Bobwhite Quail

Separate subchronic reproductive toxicity studies were conducted using mallard ducks (Anas platyrhynchos) and northern bobwhite quail (Colinus virginianus). Three groups (32/group; 16 male-female pairs) of 17-week-old ducks (F0 generation) were fed Purina Game Bird Breeder Layena diets containing mean (+/-SD) 33.2 (+/-2.7), 68.9 (+/-1.8), and 140.9 (+/-5.1) microg/g strychnine for 20 weeks, with some pairs in each group fed control diet during a subsequent 3-week recovery period. Three groups (32/group; 16 male-female pairs) of 19-week-old quail (F0 generation) were fed similar diets containing mean (+/-SD) 279.2 (+/-10.1), 557.4 (+/-43.5), and 1,113.6 (+/-46.6) microg/g strychnine for 22 weeks without a recovery period. Separate groups of ducks and quail (32/group; 16 male-female pairs) were also fed control diets (0.0 microg/g strychnine) in each study. There were 16 weekly collections of eggs for the mallard study (13 for the diet-exposure period and 3 for the recovery period), and 11 collections for the quail study. Eggs laid during the last 13 and 10 weeks of the diet-exposure periods for ducks (plus 3 weeks of the recovery period) and quail, respectively, were incubated. Each hatch of F1 generation ducklings and chicks was observed for 14 days. Key results were: (1) the no observed adverse effect levels (NOAELs) for F0 ducks and quail were 33.2 and 1,113.6 microg/g strychnine, respectively--quail showed no reproductive effects at the current doses; (2) decreased egg production and hatching success occurred for mallard hens fed mean 140.9 microg/g strychnine diets; and (3) "normal-hatching" ducklings from eggs of F0 mallards fed mean 140.9 microg/g strychnine diets suffered greater mortality than ducklings from the other diet groups. Possible mechanisms of strychnine action on avian reproduction are discussed.     

全氟辛烷磺酸对大鼠脑组织氨基酸类神经递质和谷氨酰胺合成酶的影响

目的探讨全氟辛烷磺酸(PFOS)与大鼠中枢神经系统兴奋性氨基酸和谷氨酰胺合成酶(GS酶)的剂量反应关系。方法将20只成年雄性Wister大鼠随机分为4组(对照组、4个染毒组)每组5只。大鼠染毒PFOS(12.5、25、50mg/kg)5天后,对照组给予等体积的2%吐温-80溶液,应用高效液相色谱法测定脑组织氨基酸类神经递质及谷氨酰胺合成酶的改变。结果与对照组比较,大鼠自发活动能力下降;50mg/kg体重组海马谷氨酸含量显著降低,25和50mg/kg体重组皮质谷氨酸含量显著降低;随着染毒剂量的增加海马GS酶活性增加,其中12.5mg/kg剂量组和25mg/kg剂量组明显高于对照组(P<0.05)。结论氨基酸类神经递质含量的改变是PFOS神经毒性的机制之一。     

Perfluorooctanoic Acid and Perfluorooctane Sulfonate in Liver and Muscle Tissue from Wild Boar in Hesse,Germany

Approximately 15,000 tons of wild boar meats (Sus scrofa) are consumed per year in Germany. Boar meat therefore plays a definite role in regard to human diet. Because they are omnivores and because of their high body fat quotient, wild boar may accumulate large concentrations of persistent organic compounds, such as halogenated hydrocarbons, and could thus possibly serve as bioindicators for persistent xenobiotics. In addition, consumption of wild boar meat and liver could lead to increased contaminant levels in humans. Between 2007 and 2009, we tested a total of 529 livers and 506 muscle tissue samples from wild boar for the presence of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). PFOA concentrations ≤45 μg/kg and PFOS concentrations ≤1,780 μg/kg were detected in the liver samples. PFOA concentrations ≤7.4 μg/kg and PFOS concentrations ≤28.6 μg/kg were detected in muscle tissue. Our results show that PFOS may be detected in considerably greater concentrations than PFOA in organs and tissues, which is in agreement with results from other published studies. The comparisons between both organs for the same substance, as well as the comparisons between the substances within an organ, showed clear and statistically significant differences at P < 0.0001. Assuming a tolerable daily intake value of PFOA (1.5 μg/kg bw/d) and PFOS (0.15 μg/kg bw/d) as recommended by the European Food Safety Authority, the results of model calculations based on the maximum concentrations of PFOA and PFOS found in wild boar indicate that there should be no PFC-related health danger resulting from moderate consumption of wild boar meat or liver.     

火龙果对高血脂模型大鼠的降脂作用实验研究

目的研究“紫红龙”火龙果对高血脂SD大鼠的降脂作用。方法根据TG水平将50只雄性SD大鼠随机分为5组,每组10只,设为阴性对照组、高脂模型对照组、火龙果：7．5、10．0、15．0g／kgbw3个剂量组。剂量组灌胃不同浓度的火龙果果浆,两个对照组灌胃同体积的蒸馏水。3个剂量组、高脂模型对照组动物自由进食高脂饲料,阴性对照组自由进食基础饲料。实验进行45d后处死大鼠取血清测定各组大鼠的甘油三酯（TG）、总胆固醇（CHO）、高密度脂蛋白（HDH—C）、低密度脂蛋白（LDH—C）、谷丙转氨酶（ALT）、谷草转氨酶（AST）,取肝脏称重,计算肝／体重比值,并做病理切片。结果火龙果中剂量组、高剂量组大鼠的TG、CHO、LDH—C较高脂模型组明显降低,差异有统计学意义（P〈0．05）;谷草转氨酶（AST）、肝实质重量、肝／体比值结果表明：高脂饮食除能引起大鼠的血脂升高,还能损害机体的肝脏实质,引起AST升高、肝脏增大;但随火龙果的剂量增加,肝脏受损害的程度逐渐减轻,特别是AST指标,火龙果的高剂量组已恢复至阴性组水平。结论“紫红龙”火龙果对高血脂sD大鼠具有明显的降脂作用。     

线粒体膜通透性在微囊藻毒素诱导的小鼠肝细胞凋亡中的作用

目的从线粒体膜通透性(MPT)的角度去研究微囊藻毒素(MCs)诱导小鼠肝细胞凋亡的作用机制,并揭示活性氧(ROS)在其中的作用。方法将ICR雄性小鼠随机分成4组,A组:腹腔注射生理盐水;B组:腹腔注射MC-LR 50μg/kg bw;C组:腹腔注射线粒体膜通透性抑制剂环孢霉素A(CsA)100mg/kg bw;D组:提前1小时腹腔注射CsA 100mg/kg bw后再腹腔注射MC-LR 50μg/kg bw。分离小鼠血清,检测AST、ALT含量;分离小鼠肝脏,进行小鼠肝脏DNA片段化检测、线粒体膜电位检测、ROS水平检测和Bcl-2表达水平的western blotting检测。结果在50μg/kg bw MC-LR处理组中,血清中AST、ALT水平升高,肝细胞中出现明显的DNA ladder、Bcl-2蛋白水平的表达上调、肝组织线粒体膜电位降低、组织ROS水平升高;100mg/kgbw CsA处理组小鼠各项指标没有明显变化;而预处理100mg/kg bw CsA后再腹腔注射50μg/kg bw MC-LR则可以消除肝组织DNA ladder,并且使血清AST、ALT含量,肝脏Bcl-2蛋白的表达、线粒体膜电位和ROS水平恢复到对照组的水平。结论体内环境下,抑制线粒体膜转运通道可抑制MC-LR诱导的肝细胞凋亡。     

Toxicity of acephate and methamidophos to dark-eyed juncos

The calculated, acute oral LD₅₀ of acephate and methamidophos to dark-eyed juncos (Junco hyemalis) was 106 mg/kg and 8 mg/kg, respectively. Brain cholinesterase (ChE) activity in birds that died after acephate poisoning was depressed 80% below that of control birds. Birds that died of acute methamidophos poisoning had brain ChE depression of 60%. The birds killed by acephate had brain acephate residue concentrations greater than 2 mg/kg and methamidophos concentrations usually greater than 0.25 mg/kg. Eighty percent of the birds killed with methamidophos had brain methamidophos concentrations greater than 0.1 mg/kg. The five-day feeding LC₅₀ for acephate was 1485 mg/kg. Brain ChE activities of birds which died early in the study were less depressed (51.5%) than those which died at a later date (69.6%). Brain residues of acephate and methamidophos were lower in these birds than in the birds of the acute oral LD₅₀ studies. Brain ChE activity returned to normal within three days after the birds received a single sublethal dose of acephate. These studies indicate that the amount of acephate needed to produce the ChE depression found in other investigations in most dark-eyed juncos exposed to forest applications of insecticide is about one-fifth of the LD₅₀; however, in a few birds the ChE activity may be depressed to near lethal levels.Formerly, Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture, Berkeley, CA 94701.