Residues of hormonal substances in foods of animal origin: a risk assessment

Determination of Hormonal Growth Promotants in Beef Using Liquid Chromatography-Tandem Mass Spectrometry

Hormonal growth promotants (HGPs) are a class of pharmaceutical agents commonly administered to cattle in the United States to improve growth rates of the animal, alter behavior, or to improve the desired characteristics of retail cuts of meat. There is a concern that low residual concentrations of HGPs may remain in tissue after slaughter, and consumption of tissues containing these compounds may increase the risk of adverse health outcomes, including cancer. Sensitive and selective methods are necessary to assess exposure of HGPs by populations that consume meat products from animals that may have been administered HGPs. A liquid chromatography-tandem mass spectrometry method was developed and validated to detect the low-level presence of HGPs including estradiol, testosterone, estradiol benzoate, melengestrol, melengestrol acetate, progesterone, testosterone propionate, trenbolone, trenbolone acetate, and α-zearalanol in retail cuts of meat following a liquid-liquid extraction using a high pH solution with 30-50× less mass of meat required as compared to similar approaches. Good chromatographic performance and sensitivity was achieved utilizing ammonium fluoride as a mobile phase additive without the need for derivatization. Validation parameters including accuracy, precision, recovery, matrix effects, limits of detection, limits of quantitation, linear range, and stability were determined. The limits of detection ranged from 0.1 to 1.0 ng/g, depending on the compound, with adequate accuracy and precision without the need for extensive sample preparation approaches.

Scientific Opinion on the public health hazards to be covered by inspection of meat from sheep and goats

A risk ranking process identified Toxoplasma gondii and pathogenic verocytotoxin-producing Escherichia coli (VTEC) as the most relevant biological hazards for meat inspection of sheep and goats. As these are not detected by traditional meat inspection, a meat safety assurance system using risk-based interventions was proposed. Further studies are required on T. gondii and pathogenic VTEC. If new information confirms these hazards as a high risk to public health from meat from sheep or goats, setting targets at carcass level should be considered. Other elements of the system are risk-categorisation of flocks/herds based on improved Food Chain Information (FCI), classification of abattoirs according to their capability to reduce faecal contamination, and use of improved process hygiene criteria. It is proposed to omit palpation and incision from post-mortem inspection in animals subjected to routine slaughter. For chemical hazards, dioxins and dioxin-like polychlorinated biphenyls were ranked as being of high potential concern. Monitoring programmes for chemical hazards should be more flexible and based on the risk of occurrence, taking into account FCI, which should be expanded to reflect the extensive production systems used, and the ranking of chemical substances, which should be regularly updated and include new hazards. Control programmes across the food chain, national residue control plans, feed control and monitoring of environmental contaminants should be better integrated. Meat inspection is a valuable tool for surveillance and monitoring of animal health and welfare conditions. Omission of palpation and incision would reduce detection effectiveness for tuberculosis and fasciolosis at animal level. Surveillance of tuberculosis at the slaughterhouse in small ruminants should be improved and encouraged, as this is in practice the only surveillance system available. Extended use of FCI could compensate for some, but not all, the information on animal health and welfare lost if only visual post-mortem inspection is applied.

A two-generation reproduction study to assess the effects of cows' milk on reproductive development in male and female rats

OBJECTIVE

To examine whether the considerable quantities of increased female sex hormone levels found in modern milk as a result of modern dairy farming practices are safe for human consumption.

DESIGN

Males and females of the P generation were maintained on a diet containing milk for 10 weeks before mating. Exposure to milk was continued up to the end of weaning of the F2b offspring.

SETTING

Two-generation reproduction study.

ANIMAL(S)

Male and female Wistar Galas rats.

INTERVENTION(S)

P- and F1-generation rats were mated.

MAIN OUTCOME MEASURE(S)

Fertility, fecundity, and morphology and function of reproductive organs.

RESULT(S)

Although milk had growth-promoting effects in both parents and offspring, it caused no impairments in fertility, fecundity, or reproductive organ development in either generation. However, a whole litter from a dam of the P generation was born dead, three litters in total had a pup with skeletal abnormalities, and the AGD of F2a female pups was reduced. These events occurred only in the milk-treated rats. It is unknown whether these issues had any relevance to milk or only happened by chance.

CONCLUSION(S)

Further study is required to determine whether milk from pregnant cows is completely free from adverse effects on reproductive health.