Long-term dietary exposure to copper in the population in Germany - Results from the BfR MEAL study.

The German Total Diet Study (BfR MEAL Study) measured copper in 356 foods. In 105 of these foods copper was determined separately for conventionally and organically pooled samples. Mammalian liver, nuts, oilseeds, cocoa powder and chia seeds contained the highest copper levels. Organically produced foods tended to have higher levels compared to conventionally produced foods. Children's copper exposure was between 0.04 mg/kg body weight per day (mg/kg bw/day) and 0.07 mg/kg bw/day (median). High exposure (95th percentile) ranged between 0.07 mg/kg bw/day and 0.11 mg/kg bw/day. Adult's exposure ranged between 0.02 mg/kg bw/day (median) and 0.04 mg/kg bw/day (95th percentile). Grains and grain-based products were main contributors for all age groups. Copper intake was about 10% higher in a scenario where consumers select the organically produced variants. Children's median and high exposure was above the acceptable daily intake (ADI) of 0.07 mg/kg bw/day set by the European Food Safety Authority (EFSA). However, according to EFSA's evaluation this is not of concern due to higher requirement related to growth. For adults, frequent consumers of mammalian liver exceeded the ADI in median and 95th percentile. Intake of copper-containing dietary supplements may also lead to exceedance of the ADI in all age groups.

Transfer and toxicokinetic modeling of non-dioxin-like polychlorinated biphenyls (ndl-PCBs) into accidentally exposed dairy cattle and their calves - A case report.

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that accumulate in tissues of exposed animals and humans. This case report refers ton=3 dairy cows accidentally exposed to non-dioxin-like PCBs (ndl-PCBs) of unknown origin on a German farm. At study start they had a cumulative total of 122-643 ng/g fat in milk and 105-591 ng/g fat in blood, consisting mainly of PCBs 138, 153, and 180. Two cows calved during the study and their calves were raised on their mothers' milk, resulting in cumulative exposure until slaughter. A physiologically based toxicokinetic model was developed to describe the fate of ndl-PCBs in the animals. The toxicokinetic behavior of ndl-PCBs was simulated in individual animals, including transfer of contaminants into calves via milk and placenta. Both the simulations and experimental data indicate that contamination via both routes is significant. In addition, the model was used to estimate kinetic parameters for risk assessment.

Unraveling Congener-Specific Transfer of Non-Dioxin-Like Polychlorinated Biphenyls (ndl-PCBs) from Feed into Chicken Meat.

Non-dioxin-like polychlorinated biphenyls (ndl-PCBs) are a subclass of persistent bioaccumulative pollutants able to enter the food chain. We investigated the transfer of ndl-PCBs from contaminated feed into meat and liver of fattening chickens. A total of 48 chicks were divided into five treatment and one control groups. Treated animals were fed with contaminated diets (11.7 ± 0.4 µg/kg sum of indicator ndl-PCBs; 88% dry matter (DM)) before slaughter for different subperiods of time: 16, 23, 28, 32, and 36 days for groups 1-5, respectively. One day after the end of each subperiod, three animals per group were slaughtered to determine the congener-specific ndl-PCB content. All remaining animals were fed the control feed until slaughter on day 37 to probe depuration. We used these data to generate congener-specific physiologically based toxicokinetic (PBTK) models for indicator ndl-PCBs. The models show that PCBs 28, 138, 153, and 180 form a more slowly eliminated cluster (with an observed transfer rate into meat over 74% and observed half-lives over 8.7 days) than PCBs 52 and 101 (with a transfer rate under 13% and half-lives under 2.6 days). Our simulations show that ndl-PCB levels in feed lower than 3.9 (long 56-day) or 4.4 µg/kg (short 37-day fattening period) would be necessary to ensure the current maximum level in muscle meat (fat basis), according to EU Regulations 1881/2006 and 1259/2011. The PBTK models are made available in the Python and Food Safety Knowledge Exchange formats.

Marination increases the bioavailability of lead in game meat shot with lead ammunition.

As a consequence of the toxicological lead characteristics, a reduction of its exposure should consider all sources. Game meat might contain elevated levels of lead due to the use of lead ammunition. The aim of the present study was to investigate the effects of acidic marination on the bioavailability of ammunition-derived lead in game meat (Roe deer), using the growing pig as an animal model. Furthermore, the study should provide evidence that the large-area scattering of lead particles leads to noticeable differences in the individual lead intake per game meat portion. Pigs of group A (n 7) received lead-shot game meat, which was cooked in water. Pigs of group B (n 7) received lead-shot game meat, which was first marinated (wine and vinegar) and then cooked. The lead content of both game meat preparations was equal with 0⋅77-0⋅79 mg Pb/portion. Pigs of group C (n 4) received lead-free game meat, which was also marinated and cooked. Additionally, lead acetate was administered intravenously to group D pigs (n 4). Blood samples were taken on elevated time points before and after game meat intake/i.v.-application. The acidic marination increased the bioavailability of orally ingested lead, resulting in significantly higher blood lead concentrations. The bioavailability of lead was 2⋅7 % when game meat was just cooked and 15 % when the meat was marinated before. The considerable variation of the individual blood lead concentrations suggests that an inhomogeneous distribution of ammunition-derived lead particles (in terms of size and number) causes individually non-comparable lead intakes from the consumption of game meat.

[Accidental feeding of the coccidiostat nicarbazin in layer breeder flocks - A case report]. / Versehentliche Fütterung von Legehennen-Elterntier-Herden mit dem Kokzidiostatikum Nicarbazin.

Following the accidental feeding of a compound feed containing the coccidiostat nicarbacin in layer breeder flocks (Lohmann Brown Classic), the birds displayed distinct clinical signs within a few hours. Mortality increased during the following 5 days, whereas laying performance and hatching rate of eggs during this period decreased markedly. Egg shell discoloration was observed as early as during the first day. As a consequence, an association between feeding of the coccidiostat nicarbacin and the observed symptoms was assumed. Recent studies indicate that Nicarbacin reduces the activity of aminolevulinic acid synthase type 1 (ALAS 1), which is responsible for the synthesis of protoporphyrin IX in the shell gland as main compound of brown egg shells. Reduced laying performance and increased mortality was likely due to nicarbacin-induced deregulated body temperature homeostasis and concomitant imbalances in acid-base status of the animals. The case reveals that the accidental feeding of nicarbacin to non-target animals such as laying hens and their parents may result in acute clinical symptoms. This highlights the necessity of appropriate care in handling feed additives and their premixes for specific non-target animals and should sensitize farmers and veterinarians.

Predicting the transfer of contaminants in ruminants by models - potentials and challenges.

Undesirable substances in feed can transfer into foods of animal origin after ingestion by livestock animals. These contaminants in food may threaten consumer health. Commonly, feeding trials are conducted with animals to assess the transfer of undesirable substances into animal tissues or milk. Such feeding trials explore the effects of the various physiological systems (e.g., ruminant and non-ruminant gastro-intestinal tracts) as well as different livestock production intensities on transfer. Using alternative methods to mimic the complex physiological processes of several organs is highly challenging. This review proposes a potential cascade of in vitro and ex vivo models to investigate the transfer of contam­inants from feed into foods of animal origin. One distinct challenge regarding the models for ruminants is the simulation of the forestomach system, with the rumen as the anaerobic fermentation chamber and its epithelial surfaces for absorption. Therefore, emphasis is placed on in vitro systems simulating the rumen with its microbial ecosystem as well as on ex vivo systems to replicate epithelial absorption. Further, the transfer from blood into milk must be evaluated by employing a suitable model. Finally, in silico approaches are introduced that can fill knowledge gaps or substitute in vitro and ex vivo models. Physiologically-based toxicokinetics combines the information gained from all alternative methods to simulate the transfer of ingested undesirable substances into foods of animal origin.

Lead content in wild game shot with lead or non-lead ammunition - Does "state of the art consumer health protection" require non-lead ammunition?

The toxicity of lead has been known for a long time, and no safe uptake level can be derived for humans. Consumers' intake via food should therefore be kept as low as possible. Game meat can contain elevated levels of lead due to the use of lead ammunition for hunting. A risk assessment conducted in 2010 by the German Federal Institute for Risk Assessment including various consumption scenarios revealed a possible health risk for extreme consumers of game meat hunted with lead ammunition (i.e. hunters and members of hunters' households). Babies, infants, children and women of childbearing age were identified as vulnerable group with regards to the developmental neurotoxicity of lead. It was noted, that a sound data base was required in order to refine the assessment. Therefore, the research project "Safety of game meat obtained through hunting" (LEMISI) has been conducted in Germany, with the aims of determining the concentrations of lead (as well as of copper and zinc) brought into the edible parts of game meat (roe deer (Capreolus capreolus) and wild boar (Sus scrofa)) due to using either lead or non-lead hunting ammunition, whilst concurrently taking geogenic (i.e. "background") levels of lead into account. Compared to non-lead ammunition, lead ammunition significantly increased lead concentrations in the game meat. The use of both lead and non-lead ammunition deposited copper and zinc in the edible parts of game meat, and the concentrations were in the range of those detected regularly in meat of farm animals. For the average consumer of game meat in Germany the additional uptake of lead only makes a minor contribution to the average alimentary lead exposure. However, for consumers from hunters' households the resulting uptake of lead-due to lead ammunition-can be several times higher than the average alimentary lead exposure. Non-lead bullets in combination with suitable game meat hygienic measures are therefore recommended in order to ensure "state of the art consumer health protection".

Copper and zinc content in wild game shot with lead or non-lead ammunition - implications for consumer health protection.

The aim of this study was to examine the contamination of game meat with copper and zinc and establish whether the use of alternative (non-lead) ammunition can lead to higher or unsafe levels of copper and zinc in the meat of roe deer, wild boar and red deer. The research project "Safety of game meat obtained through hunting" (LEMISI) was conducted in Germany with the purpose of examining the entry of lead as well as copper and zinc into the meat of hunted game when using either lead or non-lead ammunition. The outcome of this study shows that the usage of both lead-based ammunition and alternative non-lead ammunition results in the entry of copper and zinc into the edible parts of the game. Using non-lead ammunition does not entail dangerously elevated levels of copper and zinc, so replacing lead ammunition with alternative ammunition does not introduce a further health problem with regard to these metals. The levels of copper and zinc in game meat found in this study are in the range found in previous studies of game. The content of copper and zinc in game meat is also comparable to those regularly detected in meat and its products from livestock (pig, cattle, sheep) for which the mean human consumption rate is much higher. From the viewpoint of consumer health protection, the use of non-lead ammunition does not pose an additional hazard through copper and zinc contamination. A health risk due to the presence of copper and zinc in game meat at typical levels of consumer exposure is unlikely for both types of ammunition.

Accumulation of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in livers of young sheep.

A major part of sheep livers contains levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) above the former but to some extent also the new maximum levels (MLs) in the EU. In order to investigate the relationship between the intake of these contaminants and their accumulation in livers, kidney fat and meat, young blackhead sheep were fed with grass pellets containing PCDD/Fs at 2.5 times the maximum level. Levels of PCDD/Fs in livers were already quite high at the start of the exposure but increased 3-fold within 56d, exceeding the new product based MLs. Levels in meat and fat also increased but did not exceed the MLs. Although less elevated in the grass, both dl- and ndl-PCB levels also increased in liver and fat. Their kinetics in the tissues was less clear, potentially caused by increased levels in the straw given to the sheep during the whole experimental period. There was a clear difference in the behavior of the various congeners, the PCDFs and especially the higher chlorinated PCDFs and PCDDs showing a higher accumulation in the liver. In the case of the PCBs, this was particularly true for PCB 126. When switched to clean grass after 56d, the levels in livers and other tissues decreased to about the levels in the control sheep within 56d. This offers a potential solution for decreasing the intake of consumers.

Assessment of reference values for copper and zinc in blood serum of first and second lactating dairy cows.

The influence of different copper and zinc contents in rations on blood serum concentrations in dependence on feeding (Groups A and B) and lactation (Lactation 1 and 2) was tested in a feeding trial with 60 German Holstein cows. All animals received a diet based on maize and grass silage ad libitum. 30 cows received a concentrate supplemented with copper and zinc as recommended (Group A), whereas the other 30 animals were offered a concentrate with roughly double the amount of copper and zinc (Group B). Blood samples were taken several times during the lactation to analyse serum concentrations of copper and zinc. Copper serum concentration was influenced neither by the different feeding (11.7 mumol/L in Group A and 12.3 mumol/L in Group B) nor by the lactation (12.0 mumol/L in Lactation 1 and 12.1 mumol/L in Lactation 2). Zinc serum concentration was significantly influenced as well as by feeding (14.1 mumol/L in Group B and 12.5 mumol/L in Group A) and lactation (14.2 mumol/L in the second lactation and 12.8 mumol/L for first lactating cows). For an exact diagnosis of trace element supply, blood serum is a not qualified indicator; other sources (feedstuffs, liver, hair) must also be investigated.

Iodine concentration of milk in a dose-response study with dairy cows and implications for consumer iodine intake.

Most feed is poor in iodine and iodine supplementation of cow's diets must guarantee milk iodine concentrations for humans that contribute to prevention of the deficiency and minimize the risk of exceeding an upper limit of iodine intake. Five Holstein cows were fed four iodine doses (via Ca(Iota O(3))(2).6H(2)O). In four sequential 14-d periods, doses of 0.2 (basal diet), 1.3, 5.1, and 10.1 mg iodine kg(-1) diet dry matter (DM) were administered. Samples of milk were collected during each period; blood was also sampled from each cow for each iodine dosage. In an 18-d depletion period, a non-supplemented diet was provided. Iodine was determined by inductively coupled plasma-mass spectrometry. The iodine content of milk and serum reflected the iodine dosages in feed significantly. The levels for the four doses tested in milk were 101+/-32, 343+/-109, 1215+/-222, and 2762+/-852 microg iodine kg(-1). The total amount of iodine in milk per day was 30-40% of ingested supplemental iodine. Omitting additional iodine resulted in a short-term reduction of serum and milk iodine following an exponential decay function. The iodine supplementation of 0.5-1.5 mg kg(-1) diet DM represents the requirement of the cow, resulting in 100-300 microg iodine L(-1) milk, which optimally contributes to human supply. The maximum dietary levels of former and present EU legislations (10 and 5 mg iodine kg(-1) cow feed) increase the risk of iodine excess in humans.

Effect of zeolite A on rumen fermentation and phosphorus metabolism in dairy cows.

The aim of the present study was to determine the effect of zeolite A on several physiological parameters and on mineral metabolism in the rumino-intestinal-tract of cows. Eight double fistulated (rumen and proximal duodenum) cows were fed maize silage, grass silage and concentrate. Zeolite A was added to the ration over a period of three weeks at 0, 10 and 20 g/kg dry matter (DM). The daily feed amounts were adjusted to the current performance and varied between 3.9 and 15.5 kg/d. Rumen fluid, duodenal chyme and faeces were sampled to characterise the nutrient digestibility. Blood samples were taken to analyse the concentration of inorganic phosphate. Zeolite A supplementation led to a significantly reduced ruminal DM digestibility and fermentation of organic matter. The molar proportion of acetate in the rumen increased, and propionate as well as valerate decreased significantly after zeolite A supplementation. The concentration of the total fatty acids and ruminal pH were not affected. No effect on faecal digestion of DM, organic matter nor on calcium and magnesium digestion was observed. Otherwise the phosphorus (P) concentration in rumen fluid correlated negatively with the mean zeolite A intake (r (2) = 0.75; p = 0.0003). Further, the faecal excretion of P increased significantly for cows with the highest zeolite A dosage (36.9 g P/d) compared to the control group (29.9 g P/d). The lower digestibility of P resulted in a significantly decreased concentration of inorganic P in serum from a basal value of 2.05-1.16 mmol/l six days after starting zeolite A supplementation. The zeolite A treated cows showed a significantly higher Al concentration already in rumen fluid (14.31 and 13.84 mmol/l) compared to the control cows (6.33 mmol/l). The Al flow in the duodenum was also higher for zeolite A treated cows.

[Influence of different copper and zinc supply on their concentrations in blood serum, liver and hair of dairy cows]. / Einfluss unterschiedlicher Kupfer- und Zinkversorgung auf deren Konzentrationen in Blutserum, Leber und Deckhaar bei Milchkühen.

In a feeding trial at the Institute of Animal Nutrition of the Federal Research Institute of Animal Health (FLI) over 12 weeks with 20 cows of the German Holstein Breed the influence of different copper and zinc contents in the ration on their concentration in blood serum, liver and hair was tested. All animals received a diet based on maize- and grass silage ad libitum. The animals were divided in two groups with 10 cows each; group A received a concentrate according to their milk yield with a copper and zinc content as recommended (GfE 2001), whereas group B was offered a concentrate with roughly the double amount of copper and zinc. At the beginning and at the end of the trial a sample of blood, pigmented hair and a liver bioptate was taken from all animals to evaluate the incorporation of copper and zinc in these tissues. In serum and pigmented hair the copper concentrations did not differ between the two groups [13.4 for Group A and 12.5 micromol/L for Group B in serum respectively 6.8 (Group A) and 7.4 mg/kg DM (Group B) in pigmented hair]. Only the copper concentration in the liver was influenced by the different feeding. The higher copper content for group B resulted in a significantly higher copper concentration in the liver (506 mg/kg DM compared to 383 mg/kg DM). The liver is the best indicator organ for a sufficient copper supply. An increase in the zinc content in the ration resulted neither in higher zinc concentrations in serum (15.1 in Group B in comparison to 13.4 micromol/L for Group A) nor in higher zinc concentrations in liver (140 for Group B and 112 mg/kg DM for Group A) and pigmented hair (130 in Group A and 123 mg/kg DM in Group B). There is a significant correlation between copper intake and copper concentration in the liver (r = 0.46), whereas the correlation between zinc intake and zinc concentration in the liver is only tendencially (r = 0.23). The three tested samples serum, liver and cow hair are not qualified to reflect exactly a sufficient zinc supply.

[Influence of zeolite A supplementation during the dry period of dairy cows on feed intake, on the macro and trace element metabolism around calving and milk yield in the following lactation]. / Einfluss von Zeolith A auf die Futteraufnahme von trockenstehenden Milchkühen, auf den Mengen- und Spurenelementstoffwechsel im peripartalen Zeitraum sowie auf die Milchleistung in der folgenden Laktation.

The object of the present study was to determine the influence of zeolite A, a calcium binder from the group of the aluminosilicate, on feed intake, macro and trace element metabolism as well as the milk yield in the following lactation in dairy cows. 46 cows were allotted to 2 groups (A--control group and B--experimental group). They were fed a total mixed ration (TMR) ad libitum 2 weeks before calving. Additionally the cows in group B received 90 g zeolite A/kg dry matter (DM). The individually feed intake was registered daily. The serum was analysed for Ca, Mg, and Pi (inorganic phosphate), Fe, FFA (free fatty acid) and beta-HB (hydroxybutyrate) and the plasma for the trace elements Cu, Zn, and Mn. After calving the milk yield (FCM) and the milk composition (fat, protein, lactose and urea) were analysed. Feed intake of group B, amounting to 6.2 +/- 1.3 kg DM/d was around 48% lower as compared to 12.0 +/- 1.4 kg DM/d for group A. The zeolite addition into the TMR showed a stabilizing effect on the average Ca concentration in the serum around calving. This effect led to a significantly lower Mg concentration on the day of calving and 1 day post partum. The Pi concentration was significantly lower already after the 1st week of zeolite supplementation and on the day of calving as compared to group A. There was no essential effect of zeolite A on the trace element concentration. The depression of feed intake for group B led to a significant increase of FFA one week after beginning zeolite supplementation and of beta-HB around calving. The feed intake post partum as well as the milk yield were not affected by zeolite supplementation. Because decreased feed intake of group B after zeolite supplementation and the occurred hypophosphatemia, it is not acceptable to use zeolite A in the proved dose for preventing milk fever.

[Some serum parameters of first lactation cows in relation to their supply of macro and trace elements as well as of vitamins]. / Untersuchungen einiger Blutparameter bei erstlaktierenden Kühen in Abhängigkeit von deren Versorgung mit Mengen- und Spurenelementen sowie Vitaminen.

At the Institute of Animal Nutrition of the Federal Agricultural Research Centre (FAL) in Braunschweig a feeding trial with 30 first lactating cows (German Holstein) was realised in 2004 for a complete lactation. All animals received a diet based on maize- and grass-silage ad libitum at the rate of 60:40 (DM-base) and concentrate depending on their milk yield.The animals were fed with energy and protein as recommended (GfE 2001) and were kept in loose housing. After calving they were split randomly into two feeding groups with 15 animals each. Group 1 was fed a concentrate according to the recommendations of the GfE (2001), whereas group 2 was offered the same concentrate with roughly the double amount of calcium, magnesium, phosphorus, copper, zinc, beta-carotene and vitamins A and E. To study the influence of the different concentrates on the serum concentrations of minerals and vitamins, blood, feed and milk samples were regularly taken and analysed in the course of lactation. Significantly higher blood concentrations were detected for phosphorus, zinc and vitamin E in group 2, but therefore a direct influence of the feeding on the blood concentrations was detected only for zinc and vitamin E. Over the whole lactation the average milk yield of group 1 was 2.6 kg/day higher and the average milk fat content was reduced about 0.6 percent points compared to group 2.