Bw Day Research Articles

An updated weight of evidence approach for deriving a health-based guidance value for 4-nonylphenol.

4-Nonylphenol (NP) is a persistent estrogen-active compound. Human exposure to NP is primarily through water and food. Although risk assessments of NP have been conducted by the European Union and a few other countries, only the Danish Veterinary and Food Administration, in 2000, proposed a tolerable daily intake of 0.005mgkg-1 body weight (bw) day-1 . New data have been accumulated since then, prompting an update on the risk assessment of NP. A weight of evidence approach is recommended for use in scientific assessments by several agencies, e.g., European Food Safety Authority, etc. Based on the results of a weight of evidence approach, two methods were used to derive the health-based guidance value (HBGV) for NP in this study, namely a no observed adverse effects level/lowest observable adverse effect level method, and a benchmark dose method. Considering the considerable uncertainty of benchmark dose model fitting of the available data, a tolerable daily intake value of 0.025mgkg-1 bw day-1 was derived as a provisional HBGV for NP based on the lowest observable adverse effect level value of 15mgkg-1 bw day-1 of the renal toxicity in rats, together with the uncertainty factor of 600. However, the HBGV of NP still needs further investigation.

COMPARISON BETWEEN TWO FEEDING RATES AND THREE FEEDING FREQUENCIES FOR HYBRID SURUBIMS REARED IN CAGES

ABSTRACT This study evaluated the effects of feeding frequency and feeding rate on productive performance of hybrid surubims reared in cages with automatic feeding. Three feeding frequencies (6, 12 and 24 meals day-1), and two feeding rates (4% and 8% of body weight per day, BW day-1) were evaluated. Hybrid surubims (Pseudoplatystoma corruscans × Pseudoplatystoma fasciatum) with average weights of 24.20 ± 0.80 g were distributed in 18 cages of 1.0 m³ at a density of 60 fish m-3. Fish were fed commercial ration containing 40% crude protein, and feeding took place at night using automatic feeders. The study lasted 47 days. With a feeding rate of 4% BW day-1, the final weight (FW) of the surubims was higher when feed was supplied as 24 meals day-1 (66.92 g). However, using 8% BW day-1, the FW was greater with a feeding frequency of 12 meals day-1 (106.90 g). Regardless of feed frequency, the values of daily weight gain and standard length of surubims were higher with the feeding rate of 8% BW day-1. Therefore, the feeding rate of 8% BW day-1, provided in 12 meals day-1, provided better productive performance for hybrid surubims (Pseudoplatystoma corruscans × Pseudoplatystoma fasciatum) reared in cages.

Dietary intake of dioxins in Japan in 2016 with time trends since 1998

ABSTRACTTotal diet samples collected from seven regions throughout Japan in 2016 were analysed for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls (DL-PCBs), known collectively as dioxins. This led to estimates of the latest dietary intake of these contaminants for the general Japanese population (≥1 year old). The average daily intake of dioxins for a person weighing 50 kg, calculated at non-detected congener concentrations assumed to be equal to zero, was estimated to be 0.54 pg TEQ (toxic equivalents) kg−1 body weight (bw) day−1. This value is well below the tolerable daily intake of 4 pg TEQ kg−1 bw day−1 for dioxins in Japan. The average intake was highest from fish and shellfish, followed by meat and eggs. The TEQ contribution of the fish and shellfish group to the total dietary TEQs was significant (89%). The DL-PCBs accounted for about 67% of the dioxin intake. The latest dioxin intake level was compared with previous estimates from total diet study results obtained annually since 1998 to determine the time trends in the dietary intake of dioxins in Japan. Overall, the average dioxin intake appeared to be decreasing gradually during the period of study. The previous average intakes of dioxins ranged from 0.58 to 1.9 pg TEQ kg−1 bw day−1. The latest average intake was the lowest since 1998 and was about one-third of the average intake in 1998. This decreasing trend in the dietary intake of dioxins was mainly influenced by the decreased dioxin intakes from two food groups, fish and shellfish, and meat and eggs.

Evaluation of mycotoxins and their estimated daily intake in popcorn and cornflakes using LC-MS techniques

The occurrence of 11 mycotoxins in samples of popcorn and cornflakes was evaluated by liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS), using dynamic multiple reaction monitoring. This quick, easy, cheap, effective, rugged and safe (QuEChERS) method was modified and provided good analytical results (recoveries ranged from 79 to 119%, RSDs <21% and LOQs below the established maximum level). Popcorn samples were contaminated with fumonisins, aflatoxin B1, neosolaniol and T-2 toxin, with mean concentrations of 592, 10.2 and 10.2 μg kg−1, respectively, while cornflake samples were contaminated with only T-2 (mean 11.2 μg kg−1). The co-occurrence of fumonisin B1+ aflatoxin B1 was observed in 52% of popcorn samples and was not observed in cornflake samples. The estimated intake for the Brazilian population of total fumonisins and T-2 toxin for popcorn as the upper bound approach were 0.0051 and 0.00004 μg kg −1 bw day −1, respectively, and for the 99th percentile were 0.1943 and 0.0014 μg kg −1 bw day −1, respectively, suggesting a low risk of ingestion. However heavy consumers may be exposed to a potential risk due to fumonisins (upper bound of 4.6 μg kg−1 bw day−1).

NEPHROPROTECTIVE OF ANTHOCYANIN PIGMENTS EXTRACT FROM RED CABBAGE (BRASSICA OLERACEA L. VAR. CAPITATA F. RUBRA) AGAINST GENTAMICIN-CAPTOPRIL-INDUCED NEPHROTOXICITY IN RATS

Objective: Red cabbage (Brassica oleracea L. var. Capitata f. rubra) has a fairly high anthocyanin content and is a source of powerful antioxidants. This study is basic for the development of a nutraceutical, which has nephroprotective activity.Methods: Red cabbage was extracted using ethanol and water with a mixture of citric acid with a variation of 1, 2, and 3%. The total anthocyanin was determined with pH-differential method. The Wistar strain male rats were divided into five groups. Group 1 as a negative control, Group 2 as a positive control treated with Vitamin E dose of 400 mg/kg BW day. Groups 3–5 were treated with three different extract dose of 100, 200, and 400 mg/kg BW. Gentamicin was given intraperitoneally and captopril orally for 3 days. Extracts and Vitamin E were administrated orally for 15 days after induction of gentamicin-captopril. Nephroprotective activity was determined by measuring the levels of serum creatinine, blood ureum, and macroscopic kidney.Results: The combination of 96% ethanol and citric acid 3% showed the percent of free radical 2,2-diphenyl-1-picrylhydrazyl arrest of 75.23% and contained 53.49 ± 5.01 mg/L of total anthocyanin. The anthocyanin pigment from red cabbage extract can decrease the levels of creatinine and ureum, which dose of 100 mg/kg BW showed the highest value of 48.72%. There were differences in the macroscopic morphology in the rat kidney.Conclusion: Based on the results, we concluded that ethanol with 3% citric acid produced higher anthocyanin and showed nephroprotective activity.

Fast and simple determination and exposure assessment of bisphenol A, phenol, p-tert-butylphenol, and diphenylcarbonate transferred from polycarbonate food-contact materials to food simulants

Polycarbonate (PC) plastics find extensive use in baby bottles, food storage containers, and various kitchen items. Possibly hazardous chemicals, bisphenol A (BPA), phenol, p-tert-butylphenol (TBP), and diphenylcarbonate (DPC), are source materials or by-products from PC production. Therefore, a fast and simple analytical method was developed to determine and assess the exposure of BPA, phenol, TBP, and DPC transferred from PC food-contact materials to four different food simulants (water, 4% acetic acid, 50% ethanol, and n-heptane) at different temperatures. The method was validated in terms of limit of detection (LOD) and quantification (LOQ), recovery, and precision for the detection of BPA, phenol, and TBP using HPLC-FLD and of DPC using HPLC-UV. BPA, phenol, TBP, and DPC concentrations transferred from 200 PC samples to food simulants were determined. The highest migration levels of BPA (54.3 μg L−1) and phenol (43.8 μg L−1) were found in 50% ethanol at 70 °C. TBP did not migrate to any simulant. DPC did not show any migration from PC samples into water and only migrated from a cup to 4% acetic acid at 70 °C and 100 °C, whereas migration occurred from several cups, ladles, spoons, and tongs to 50% ethanol and to n-heptane at 25 °C. Food simulants and temperature were the crucial factors for the migration of BPA and phenol from PC samples. Estimated daily intakes (EDIs), based on food consumption and food-type distribution factors, for BPA, phenol, and DPC were calculated to be 0.007, 0.001, and 2.5 × 10−4 μg kg−1 bw day−1, respectively.

Dietary exposure and risk assessment of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls of the population in the Region of Valencia (Spain)

ABSTRACTDietary exposure of the Valencia Region population to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and PCBs was assessed in the Region of Valencia in 2010–2011. A total of 7700 food samples were collected. Occurrence data were combined with consumption data to estimate dietary exposure in adults (>15 years of age) and young people (6–15 years of age). The estimated intake was calculated by a probabilistic approach. Average intake levels (upper-bound scenario) were 1.58 and 2.76 pg toxic equivalent (TEQ) kg−1 body weight (bw) day−1 for adults and young people, respectively. These average intakes are within range of the tolerable daily intake of 1–4 pg WHO-TEQ kg−1 bw day−1 recommended by WHO, and slightly above the tolerable weekly intake (TWI) of 14 pg TEQ kg−1 bw week−1 and the Provisional tolerable monthly intake of 70 pg TEQ kg−1 bw month−1 set by the Scientific Committee on Food and the Joint FAO/WHO Expert Committee on Food, respectively. These results show that the contamination levels in food and therefore the exposure of the general population to PCDD/Fs and PCBs have declined in this region and therefore show the efficiency of the European risk-management measures. In terms of risk characterisation, the results showed that, under the upper-bound scenario, 22% of the adult and 58% of the young people population could exceed the TWI.

Imidacloprid induced toxicity in ovary of female wistar rats in two generations

In present study the effect of oral administration of imidacloprid over two generations on the ovary of female Wistar rats was assessed. Female rats were divided into 3 groups. Group 1, as control, was given corn oil only while imidacloprid was administered in group 2 and 3 @ 10 and 20 mg kg−1 bw day1, respectively. A disruption in estrous cyclicity was observed with a prolonged diestrous in both F1 and F2 generation. The weight of ovary decreased significantly in treated female rats of F2 generation. Histopathology of ovary of groups 2 and 3 revealed different stages of follicles. Percentage atresia of follicles was found higher in treated rat ovaries as compared to their respective control rats in both the generations. The results indicate that no observed effect level of imidacloprid for two generations female reproductive toxicity is 10 mg kg−1 bw day−1.

Alkylphenols and alkylphenol ethoxylates in dust from homes, offices and computer laboratories: Implication for personal exposure via inadvertent dust ingestion

Abstract In the present study, the levels of alkylphenols (APs) and alkylphenol ethoxylates (APEs) in indoor dust of three different microenvironments were measured and daily intake via dust ingestion estimated. Alkylphenols and alkylphenol ethoxylates were extracted with the aid of sonication and analyzed by gas chromatography mass spectrometry after heptafluorobutyric anhydride derivatization. The concentration values of these pollutants ranged from 1918–10 935 ng g −1 ; 343–12 438 ng g −1 and 1122–15 324 ng g −1 in dust samples from homes, computer laboratories and offices, respectively. In all the microenvironment studied, di -NPE and mono- NPE were the most abundant isomers suggesting widespread use of NPE-based consumer products in the studied microenvironments. The daily exposure dose (DED) was estimated using min, mean and max concentrations of APs and APEs detected in respected microenvironments. The worst case scenario for the exposure of APEs was highest for toddlers at 146 ng kg −1 bw day −1 followed by teenagers at 11.3 ng kg −1 bw day −1 and adults at daily exposure of 8.53 ng kg −1 bw day −1 . Though the daily exposure doses are low, there is a cause for concern as these surfactants are not regulated in many developing countries and their use may be increasing.

Estimated Dietary Intakes of Toxic Elements from Four Staple Foods in Najran City, Saudi Arabia.

Exposure of the inhabitants of Najran area in Saudi Arabia to the toxic elements As, Cd, Cr, and Pb through foods has not been previously investigated. Exposure to such elements is an important public health issue, so the study described here was performed with the aim of determining estimated dietary intakes (EDIs) for these metals in Najran area. The As, Cd, Cr, and Pb concentrations in four staple foods (rice, wheat, red meat, and chicken) were determined by inductively coupled plasma-mass spectrometry. A food frequency questionnaire (FFQ) was completed by 80 study participants. These data were used to estimate dietary intakes of the metals in the four staple foods. The mean As, Cd, Cr, and Pb EDIs in the four food types were 1.1 × 10−6–2.6 × 10−5, 1.42 × 10−5–2.2 × 10−4, 3.4 × 10−4–8.0 × 10−4, and 2.3 × 10−5–2.1 × 10−3 mg/kg bw day, respectively. Hazard Quotients (HQ) for all elements did not exceed one. The highest Pb concentration was found for chicken and the source of this toxic element in this food needs to be investigated in the future. The lowest As concentration was found for wheat highest in rice. The EDIs for all elements in the four food types were below the provisional tolerable weekly intakes set by the World Health Organization (WHO).

Organophosphorus flame retardants (PFRs) and phthalates in floor and road dust from a manual e-waste dismantling facility and adjacent communities in Thailand

ABSTRACTThis study was undertaken to investigate levels of organophosphorus flame retardants (PFRs) and phthalates in floor and road dust from a manual e-waste dismantling facility and nearby communities in Thailand. Concentrations of Σ10 PFRs and Σ6 phthalates in floor dust from the facility were approximately 36–1,700 and 86,000–790,000 ng g−1, whereas those from the communities were about 13–9,200 and 44,000–2,700,000 ng g−1, respectively. The highest content of Σ10 PFRs (9,200 ng g−1) and Σ6 phthalates (2,700,000 ng g−1) in indoor dust was both detected in the dust sampled from a house with no prevailing winds located 350 m northeast of the facility. Levels of Σ10 PFRs and Σ6 phthalates in road dust from the facility were around 1,100–2,100 and 40,000–670,000 ng g−1, while those from the residences were about 650–2,000 and 27,000–650,000 ng g−1, respectively. Concentrations of Σ10 PFRs (2,100 ng g−1) and Σ6 phthalates (670,000 ng g−1) in road dust were greatest in the dust collected from the facility. For the distributional pattern, TBEP (tris (2-butoxyethyl) phosphate) was the main PFR in residential dust, whereas TPP (triphenyl phosphate) was the major PFR in facility dust. TBEP was also found to be the most prominent PFR in all road dust samples. Furthermore, DEHP (di-2-ethylhexyl phthalate) was the most abundant phthalate congener in both floor and road dust samples. Under realistic high-end scenarios of environmental exposure to DEHP, Thai toddlers (25.29 µg kg−1 bw day−1) in the adjacent communities were exposed above the US EPA's (United States Environmental Protection Agency) reference dose (RfD) for this congener (20 µg kg−1 bw day−1). Our data reveal that the PFR and phthalate-containing products at the residences are a likely substantial source of PFRs and phthalates to the surrounding indoor environment, and humans can be exposed to PFRs and phthalates in their dwellings via the settled floor dust.

Effect of dietary protein levels and feeding rates on the growth and health status of juvenile genetically improved farmed tilapia (Oreochromis niloticus)

A 2 × 3 factorial study was conducted to investigate the effects of dietary protein levels (DPLs) and feeding rates (FRs) on the growth and health status of juvenile genetically improved farmed tilapia (GIFT), Oreochromis niloticus. Triplicate tanks of fish (initial weight 15.87 ± 0.11 g) were fed diets containing 25 or 35% protein at rates of 3, 5, or 7% body weight per day (BW day−1) for 8 weeks. At the end of the feeding trial, the results showed that fish growth (final mean weight 34.61–81.07 g) and condition factor (3.39–4.45 g cm−3) increased with the DPLs and FRs. Feed efficiency (FE, 0.48–0.88) increased as DPLs increased but decreased as FRs increased; the opposite trend was observed for feed cost (FC, 3.24–5.82 CHN Yuan kg−1) and hepatosomatic index (0.98–2.33%). Apparent protein retention efficiency (APRE, 23.92–38.78%) was reduced by high FR. A 35% protein diet resulted in higher (P 0.05), except urea nitrogen levels, which were affected by DPLs (P < 0.05). Moreover, the size of hepatocytes and the area ratio of hepatocyte vacuoles were enlarged (P < 0.05), whereas the area ratios of the nucleus and cytoplasm were reduced (P < 0.05) with increasing FRs. These results suggested that the optimal feeding strategy for juvenile GIFT is 35% protein diet at 5% BW day−1.

Gender-specific association between dietary acid load and total lean body mass and its dependency on protein intake in seniors.

The aim of this study was to determine if dietary acid load is associated with total lean body mass in male and female seniors age ≥60years. We investigated 243 seniors (mean age 70.3±6.3; 53% women) age ≥60years who participated in the baseline assessment of a clinical trial on vitamin D treatment and rehabilitation after unilateral knee replacement due to severe knee osteoarthritis. The potential renal acid load (PRAL) was assessed based on individual nutrient intakes derived from a food frequency questionnaire. Body composition including percentage of total lean body mass (%TLM) was determined using dual-energy X-ray absorptiometry. Cross-sectional analyses were performed for men and women separately using multivariable regression models controlling for age, physical activity, smoking status, protein intake (g/kg BW per day), energy intake (kcal), and serum 25-hydroxyvitamin D concentration. We included a pre-defined subgroup analysis by protein intake (<1g/kg BW day, >1g/kg BW day) and by age group (<70years, ≥70years). Adjusted %TLM decreased significantly across PRAL quartiles only among women (P trend=0.004). Moreover, in subgroup analysis, the negative association between the PRAL and %TLM was most pronounced among women with low protein intake (<1g/kg BW per day) and age below 70years (P=0.002). Among men, there was no association between the PRAL and %TLM. The association between dietary acid load and %TLM seems to be gender-specific, with a negative impact on total lean mass only among senior women. Therefore, an alkaline diet may be beneficial for preserving total lean mass in senior women, especially in those with low protein intake.

Survey of mycotoxins in retail market cereals, derived products and evaluation of their dietary intake

In current study a total 229 samples of cereal products, available in retail markets of main cities of Punjab, Pakistan were collected for the analysis of mycotoxins. The analysis was performed using reverse phase HPLC with fluorescence detector. The results have shown that 121 (53%) out of 229 samples of cereal products have found positive for aflatoxin B1 (AFB1) and total aflatoxins (AFs). Samples of 22 and 12% were found higher than the maximum level for AFB1 and total AFs. The highest level of AFB1 and total AFs was found in porridge samples i.e 3.90 ± 0.039 μg kg−1 and 5.60 ± 0.005 μg kg−1, respectively. About 115 (50%) out of 229 samples of cereal products were found positive with ochratoxin A (OTA) and 26% samples were found to be higher than the maximum level of 3 μg kg−1. About 130 (57%) samples of cereal were found contaminated with zearalenone (ZEN) and 31% of samples were found higher than the maximum level of 50 μg kg−1. The highest mean level of 21.45 ± 1.90 μg kg−1 of ZEN was found in Suji (Semolina) samples. The estimated average exposure dose of AFB1, OTA and ZEN based on our daily food consumption data were 3.50, 3.85 and 29 ng kg−1 bw day−1 found in some cereal samples, respectively. The calculated excess risk of liver cancer incidence by ingestion of cereals containing AFB1 was 1.66 per 100,000 adults per year.

Bioaccessibility and Human Exposure Assessment of Cadmium and Arsenic in Pakchoi Genotypes Grown in Co-Contaminated Soils.

In many countries cadmium (Cd) and arsenic (As) commonly coexist in soils contaminated by mining activities, and can easily enter the human body via consumption of leafy vegetables, like the popularly consumed pakchoi (Brassica chinensis L.), causing major health concerns. In the present study, bioaccessibility and human exposure of Cd and As were assessed in twenty genotypes of pakchoi cultured at two different levels of co-contamination to identify low health risk genotypes. The bioaccessibilities of Cd and As represent a fraction of the total metals content could be bioaccessible for human, in the present study, significant differences in pakchoi Cd and As bioaccessibility were observed among all tested genotypes and co-contaminated levels. Cd and As bioaccessibility of pakchoi were in the ranges of 24.0–87.6% and 20.1–82.5%, respectively, for in the high level co-contaminated soils, which was significantly higher than for low level co-contaminated soils with 7.9–71.8% for Cd bioaccessibility and 16.1–59.0% for As bioaccessibility. The values of bioaccessible established daily intakes (BEDI) and the total bioaccessible target hazard quotients (TBTHQ) of Cd and As were also considerably higher in high level co-contaminated soils than in low level co-contaminated soils. Two genotypes (Meiguanqinggengcai and Zhenqing60F1) contained relatively low concentrations and bioaccessible Cd and As and, their BEDI and TBTHQ for Cd and As ranged below the tolerable limits set by the FAO/WHO (BEDI of Cd < 0.83 μg kg−1 bw day−1, BEDI of As < 3 μg kg−1 bw day−1) and United States Environmental Protection Agency (TBTHQ for Cd and As < 1), this applied for both levels of co-contaminated soils for adults and children. Consequently, these findings suggest identification of safe genotypes in leafy vegetable with low health risk via genotypic screening and breeding methods could be a useful strategy to ensure the safety of food crops grown in those Cd and As co-contaminated fields due to mining activities.

Natural occurrence of patulin in different fruits, juices and smoothies and evaluation of dietary intake in Punjab, Pakistan

The current study is focused to investigate the natural presence of Patulin (PAT) in various fruits, juices and smoothies marketed and consumed in Pakistan. A total of 237 samples of fruits, juices and smoothies were analysed using isocratic HPLC with UV detector. The results have shown that 136 out of 237 (57.4%) samples have found positive with PAT contamination with levels ranged from 0.04 to 1100 μg kg−1. The highest mean level of PAT was found in red globe grapes i.e. 921.1 ± 22.4 μg kg−1. About 33.8% samples have levels of PAT with concentration above the permissible regulations of European Union (EU) i.e. 50 μg kg−1. The dietary intake of PAT from fruits, juices and smoothies were 0.0049, 0.0016 and 0.0014 μg kg−1 bw day−1 with hazard quotient (HQ) value of 1.22, 0.40 and 0.35%, respectively. The incidence and occurrence of PAT in fruits and fruits products have high and need urgent attention for comprehensive survey. The results of present study would be useful for farmers, traders, and consumers.

Creep feeding effects on male Nellore calves influencing behavior and performance of their dams.

The objective of the present study was to evaluate the effect of different schemes of calves' supplementation in a creep feeding system, on the behavior of Bos indicus calves and dams, and also the influence of the calves' supplementation on dams' performance. Forty-eight Nellore male calves (147±7kg body weight and 3months of age) in the suckling phase and their dams (476±9kg and 6years of age) were studied in a completely randomized design. The experiment was divided into two periods of 71days. The treatments were 5- and 10-g supplement dry matter (DM)/kgBWday offered in periods 1 and 2, respectively (5S/10S); 10- and 5-g supplement DM/kgBWday offered in periods 1 and 2, respectively (10S/5S); 7.5-g supplement DM/kgBWday in both periods 1 and 2 (7.5S); and mineral mix ad libitum in both periods 1 and 2 (MM). No differences (P<0.05) in body condition score (BCS), final body weight (FBW), and average daily gain (ADG) were found in dams' performance. Calves from MM treatment spent more time (P<0.05) grazing than the supplemented calves from 5S/10S and 10S/5S treatments, in the first period. No difference in suckling time was found between the treatments (P>0.05) in the first evaluated period. Calves from 10S/5S treatment spent more time suckling and less time eating supplements (P<0.05) than 5S/10S treatment animals, in the second evaluated period. Dams of MM treatment's calves had more idle time and lower grazing time when compared with the mothers of calves from 5S/10S and 10S/5S treatments. It was concluded that different schedules of Nellore calves' supplementation on pasture do not affect their mothers' performance, and supplementation decreases the grazing time of calves in the suckling phase.

Survey of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho-polychlorinated biphenyls in US meat and poultry, 2012–13: toxic equivalency levels, patterns, temporal trends and implications

ABSTRACTThe US Department of Agriculture (USDA) conducts a statistically based survey of the domestic meat supply (beef, pork, chicken and turkey) to determine current levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and non-ortho-polychlorinated biphenyls (no-PCBs) every 5 years. Fat samples for each slaughter class were collected from US federally licensed slaughter facilities. The samples were processed and analysed for 17 PCDD/Fs and three no-PCBs. The sum of PCDD, PCDF and no-PCB toxic equivalencies (sum-TEQ) calculated using 2005 toxic-equivalency factors for all slaughter classes ranged from non-detect (n.d.) to 6.47 pg TEQ g–1 lipid. The median sum-TEQs, when n.d. = 0.5 LOD, for beef, pork, chicken and turkey were 0.66, 0.12, 0.13 and 0.34 pg TEQ g–1 lipid respectively. A comparison of the current survey with the previous three surveys shows a declining trend, with decreasing differences between medians; differences between the median sum-TEQs from 2007–08 and 2012–13 were –10%, –29%, –33% and –25% for beef, pork, chicken and turkey respectively. Several beef samples underwent further characterisation and congener patterns from these beef samples suggested pentachlorophenol treated wood as the likely exposure source. US consumer exposure to these compounds is relatively low and no slaughter class contributed more than 26% to the US Environmental Protection Agency (USEPA) chronic oral reference dose of 0.7 pg TEQ kg–1 bw day–1.

Identification, characteristics and human exposure assessments of triclosan, bisphenol-A, and four commonly used organic UV filters in indoor dust collected from Shanghai, China

Indoor dust is a very significant medium to understand human exposure of emerging contaminants. A novel and robust analytical method to measure the amounts of six personal care products (PCPs) (triclosan, bisphenol-A and four commonly used organic ultraviolet (UV) filters) simultaneously in indoor dust is developed in this paper. Target analytes were extracted using accelerated solvent extraction. After sample cleanup by solid-phase extraction (SPE), the extracts were derivatized and analyzed using gas chromatography-tandem mass spectrometry. The method detection limits achieves 0.16–0.62 pg g−1 (except for 4-methylbenzylidene camphor with 3800 pg g−1). The method was successfully applied to the analysis of 110 indoor dust samples from Shanghai, China. Results showed that the PCPs were found in most of the samples analyzed. The concentrations of the most analytes are relatively lower than those reported in USA, Japan, and European countries. The median concentration of octocrylene (OC) (1170.4 ng g−1) was found to be nearly 5–10 times higher than those of other analytes. The significantly higher concentration of ∑PCPs was observed in indoor dusts from residences than from offices (P < 0.05). The human exposure was analyzed by calculate the estimated daily intakes (EDI) of PCPs through dust ingestion for various age groups. The EDI of the target analytes for infants ranged from 0.85 to 6.18 ng kg−1 -bw day−1 and 0.07–0.49 ng kg−1 -bw day−1 for adults, respectively. This is the first study to report the doses of human exposure to UV filters in China.

Effects of feeding rates on growth, feed utilization, and body composition of juvenile Pseudobagrus ussuriensis

An 8-week feeding trial was conducted to investigate the effects of feeding rates on growth, feed utilization, and body composition of juvenile Pseudobagrus ussuriensis. Juvenile P. ussuriensis (initial body weight of 2.30 ± 0.01 g) were distributed into 15 tanks, and each tank was stocked with 30 fish. Satiation feeding (3.57% BW day−1) was determined by the point of cessation of voluntary feeding activity by fish. Five treatments that included triplicate groups were prepared for this study: 100% (satiation), 75, 50, and 25% of satiation groups and unfed group. The results indicated that weight gain (WG) and specific growth rate (SGR) increased with increasing feeding rates. WG and SGR of fish fed to satiation were significantly higher than that of fish fed to 50 and 25% of satiation and unfed fish (P 0.05). Feed efficiency (FE) and protein efficiency ratio (PER) of fish fed to 75% of satiation were significantly higher than that of fish fed other groups. There was a trend towards increased whole-body crude lipid and decreased whole-body moisture with increasing feeding rates, while whole-body protein content was not significantly affected by feeding rates. Condition factor and hepatosomatic index were increased with increasing feeding rates (P < 0.05), while there was no significant difference in viscerosomatic index with increasing feeding rates. Considering these experimental results, it can be concluded that the optimum feeding rate for growth of juvenile P. ussuriensis could be lowered to 75% of satiation without growth suppression.