PubMed Health⌕ Search

Biomedical subjects

L Tollefson

Publications and source records attributed to L Tollefson.

At least 19 recordsLinked to original sources

Health implications of residues of veterinary drugs and chemicals in animal tissues.

The animal drug approval process in the United States is based upon the premise that the presence of drug residues in meat and poultry above tolerance is a public health hazard. Tolerances represent the maximum level of concentration of antimicrobials permitted in animal tissues at the time of slaughter. The tolerances are intended to ensure that residual drugs will have no harmful effects if ingested. The purpose of this article is to present existing evidence of the acute and chronic health consequences that may occur because of food of animal origin contaminated with illegal residues above the tolerance. The impact of food-borne drug residues on the gut microflora, residue detection limitations, and the responsibility of the veterinary practitioner in ensuring food safety is discussed.

Abnormalities, Drug-Induced↗

Producer quality assurance programs.

Essentially all animal commodity organizations have established quality assurance programs designed to ensure food safety and quality. Most of these programs were originally implemented to address problems with veterinary drug residues. Many of the current programs have or plan to include food safety critical control points with specific guidelines on how to control or reduce pathogen load. The continued focus placed on food safety by today's consumer demands that American producers ensure that their commodities are wholesome, safe, and of high quality in order to remain competitive in the global marketplace. Veterinarians should recognize that it is important to encourage food animal producers to participate in quality assurance programs for their clients' economic health and for food safety and protection of public health. Commodities certified as being produced under good production practices or by producers certified as following a recognized and validated quality assurance program often bring a premium price. Also, some slaughter establishments are beginning to require producers to be certified as practicing under a recognized quality assurance program before animals are accepted for processing. This practice is being driven partially by the demands placed on slaughter establishments by the US Department of Agriculture's implementation of the Pathogen Reduction, Hazard Analysis and Critical Control Point Systems regulation. Regardless of why producer trade association quality assurance programs have come into existence, veterinarians should promote the programs as an excellent mechanism to help ensure everyone's goal of a safe, wholesome food supply.

Animals↗

Public health aspects of antibiotic resistance monitoring in the USA.

Treatment of food-producing animals with antimicrobial agents that are important in human therapy may present a public health risk by the transfer of resistant zoonotic pathogens or resistant genes from animals to humans via consumption of contaminated food. Resistant bacteria can diminish the effectiveness of antibiotics and demand the use of more expensive or less safe alternatives. In 1996, the U. S. Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and the Department of Agriculture (USDA) established the National Antimicrobial Resistance Monitoring Program to prospectively monitor changes in antimicrobial susceptibilities of zoonotic enteric pathogens from human and animal clinical specimens, from healthy farm animals, and from carcasses of food-producing animals at slaughter plants. Data resulting from the monitoring program will be used to redirect antimicrobial drug use, primarily through educational initiatives directed at health practitioners, in order to diminish the development and spread of resistance. Veterinary testing is conducted at USDA's Agricultural Research Service and CDC's Foodborne Disease Laboratory is testing human isolates under contract to FDA. Both the CDC and USDA laboratories are using a semi-automated system (Sensititre, Accumed, Westlake, Ohio) for testing susceptibilities of the isolates to 17 antimicrobial agents on a minimum inhibitory concentration plate. Comparable methods for isolate handling are used in both laboratories. This paper describes the development, implementation, and objectives of the National Antimicrobial Resistance Monitoring Program, presents initial data generated by the program, and discusses future plans.

Animals↗

Food borne disease summary by food commodity.

Microbial pathogens may be transmitted to humans via food animals and food animal products. A quick reference table is presented to provide easy access to food safety information related to the major food animal product areas. Included in the table are the pathogens, mode of transmission, public health impact, and control and prevention strategies for poultry, beef, dairy products, and pork.

Animals↗

National surveillance for antibiotic resistance in zoonotic enteric pathogens.

Treatment of food-producing animals with antimicrobial agents that are important in human therapy may present a public health risk by the transfer of resistant zoonotic pathogens from animals to humans. Resistant bacteria can diminish the effectiveness of antibiotics and demand the use of more expensive or less safe alternatives. In 1996, the Centers for Disease Control (CDC), United States Department of Agriculture (USDA), and Food and Drug Administration (FDA) established the National Antimicrobial Monitoring System to prospectively monitor changes in antimicrobial susceptibilities of zoonotic pathogens from human and animal clinical specimens, healthy farm animals, and carcasses of food-producing animals at slaughter plants. This article describes the development, implementation, and objectives of the monitoring system and presents initial data generated by the system.

Animals↗

Therapeutic antibiotics in animal feeds and antibiotic resistance.

Recent statutory changes involving animal drugs are expected to facilitate the therapeutic use of antibiotics in animal feeds in the United States of America. The use of antibiotics in animal feeds is controversial due to the potential development of resistant bacterial pathogens in food-producing animals which are exposed to the antibiotics and the resultant public health risk. Zoonotic micro-organisms can be transmitted to humans through contact with animal populations, either directly or through the consumption of contaminated food. Recommendations to address the public health concerns include the strengthening of professional education in the areas of infectious diseases and the appropriate selection and use of antimicrobial agents, the development of a comprehensive food safety education programme for food-animal veterinarians and animal producers, and the development of surveillance programmes to monitor antimicrobial resistance among zoonotic pathogens. Early identification of emerging resistance can facilitate a timely and appropriate public health response.

Animal Feed↗

Public health impact on drug residues in animal tissues.

Consumers have expressed concern regarding the health impact of drug residues in their food. Animal residues in animal tissues above the legal tolerance clearly have an impact on human health. Tolerances represent the maximal level or concentration of antimicrobial residues permitted in animal tissues at the time of slaughter. The tolerances are intended to ensure that residual drugs will have no harmful effects if ingested. This paper describes the existing evidence for specific health hazards for certain pharmacological classes of drugs and explains the risks associated with drug residues in meat and poultry above the established tolerance. The primary focus is on possible public health consequences that may occur as a result of acute exposure to illegal residues. In addition, long-term effects are discussed with added comments about the effect of residues on the intestinal flora. Most residues of veterinary drugs occur in food at such low levels that they rarely pose a chronic or long-term health hazard to consumers. The importance of food safety through the reduction of residues in our food supply cannot be overemphasized. Food safety remains a major challenge confronting contemporary society.

Animals↗

Nutrition: a cofactor in HIV disease.

The relationships among nutritional status, infectious disease, and the immune system suggest that nutrition may be a cofactor in human immunodeficiency virus (HIV) progression. We examined nutrition as a cofactor in HIV disease by reviewing the current literature on the interactions of nutrition, infectious disease processes, and immune system dysfunction. Studies demonstrate that poor nutritional status and infection affect the immune system and interact with each other. This relationship leads to the development of opportunistic infections and malignancies, which may result in a diagnosis of acquired immunodeficiency syndrome. Moreover, evidence from our review indicates that nutritional status may play a role in HIV disease progression. We recommend that clinical trials be conducted to evaluate general malnutrition and the efficacy of supplementation with specific nutrients at various stages of HIV disease.

HIV Infections↗

Foodborne bacterial infections in individuals with the human immunodeficiency virus.

The literature contains reports documenting a foodborne etiology for bacterial infections caused by Salmonella spp, Listeria monocytogenes, Campylobacter jejuni, and Vibrio spp in individuals with the human immunodeficiency virus (HIV). The incidence of these infections and the life-threatening complications that result are elevated in people with HIV infection. We present practical recommendations to prevent foodborne illnesses and the resulting complications, including gastroenteritis, bacteremia, meningitis, and death. We suggest that patients with HIV infection be counseled to avoid foods at high risk for harboring bacterial pathogens and to use careful sanitary practices in food preparation.

AIDS-Related Opportunistic Infections↗

Vitamin and mineral supplementation during pregnancy.

To determine the prevalence of individual vitamin and mineral supplement use during pregnancy and their relationships with selected characteristics of mothers, data from the 1988 National Maternal and Infant Health Survey were analyzed. The responses of 18,549 mothers were used in the analysis, which consisted of both univariate and multivariate statistical analyses. The prevalence of use for each of six supplements varied from 1.89% for zinc to 33.45% for iron. The use of these supplements did not appear to be strongly intercorrelated. Young age was associated with iron use, black race was associated with iron and vitamin A supplementation, and prenatal care and Women with Infants and Children food were associated with iron and vitamin A intake. Smoking was associated with folic acid and iron use, alcohol consumption was associated with folic acid use, and low family income was associated with iron use. The findings of the study may be useful in the future for more specific epidemiologic and clinical studies on supplementation during pregnancy.

Adolescent↗

Health claims on food labels.

Food and drug law requires that the ingredients in most foods be disclosed on their labels, but until recently there was no requirement that nutrition information be provided. The Nutrition Labeling and Education Act of 1990 (NLEA), passed on November 8, 1990, mandated the Food and Drug Administration to establish regulations requiring most foods to have a uniform nutrition label showing the amount of calories, calories from fat, total fat, saturated fatty acids, cholesterol, total carbohydrates, complex carbohydrates, sugars, fiber, protein, and sodium. The Act also establishes the circumstances under which content claims and disease claims may be made about nutrients in food. This paper briefly discusses recent changes in the food label brought about by the NLEA and focuses on health claims on food labels.

Food Labeling↗

Multiple chemical sensitivity: controlled scientific studies as proof of causation.

Multiple chemical sensitivity is an environmental illness that demands exacting methods of diagnosis. Proposed associations between symptoms and specific substances, whether to one substance or to multiple chemicals, need to be critically examined through adequately designed scientific studies. Appropriate methods for controlled scientific study of adverse reactions to chemicals are discussed as well as the Food and Drug Administration's (FDA's) experience with aspartame as an example of the need for controlled scientific studies to refute or confirm anecdotal evidence. Since 1986 the FDA has received reports of 265 cases of epileptic seizures temporally associated with the ingestion of aspartame. Information obtained from the complainants' medical records as well as data on consumption patterns, temporal relationships, and challenge tests do not support the claim that the occurrences of the seizures are linked to consumption of aspartame. In addition, two double-blind, placebo-controlled crossover studies failed to demonstrate an association between epileptic seizures in children and adults and the ingestion of aspartame.

Adult↗

Risk assessment for aflatoxin: an evaluation based on the multistage model.

Lifetime cancer potency of aflatoxin was assessed based on the Yeh et al. study from China in which both aflatoxin exposure and hepatitis B prevalence were measured. This study provides the best available information for estimating the carcinogenic risk posed by aflatoxin to the U.S. population. Cancer potency of aflatoxin was estimated using a biologically motivated risk assessment model. The best estimate of aflatoxin potency was 9 (mg/kg/day)-1 for individuals negative for hepatitis B and 230 (mg/kg/day)-1 for individuals positive for hepatitis B.

Adult↗

Eating as a hazard to health: preventing, treating dental injuries caused by foreign objects in food.

The Food and Drug Administration maintains a passive surveillance system for reporting and follow-up of complaints related to food items. The most commonly reported complaint is the discovery of foreign objects in food. The most common injuries are abrasions to the throat and buccal mucosa. Although dentists are qualified to treat oral injury resulting from foreign object ingestion, more physicians than dental professionals treat soft tissue trauma.

Digestive System↗

An analysis of FDA passive surveillance reports of seizures associated with consumption of aspartame.

Aspartame, the methyl ester of the dipeptide formed from combining phenylalanine and aspartic acid, was approved by the US Food and Drug Administration (FDA) in July 1981. FDA monitors complaints from consumers and health professionals through the Adverse Reaction Monitoring System, a passive surveillance program FDA has received 251 reports of seizures that have been linked to ingestion of aspartame by consumers. In most cases, information obtained from the complainants' medical records as well as data on consumption patterns, temporal relationships, and challenge tests did not support the claim that the occurrences of the seizures were linked to consumption of aspartame.

Adult↗