food and nutritional toxicology pdf

Food And Nutritional Toxicology Pdf

File Name: food and nutritional toxicology .zip
Size: 14958Kb
Published: 03.05.2021

It seems that you're in Germany.

For questions regarding this document, please contact Jin Young Park at , e-mail address jinyoung. It does not create or confer any rights for or on any person and does not operate to bind FDA or the public. You can use an alternative approach if the approach satisfies the requirements of the applicable statutes and regulations. The purpose of this document is to provide a brief summary of recommendations for the minimum toxicity tests to be performed for safety evaluation of direct food additives and color additives used in food based on their levels of concern. Information in this document can be used as general guidance for the determination of concern levels, as well as the extent and types of toxicity testing for direct food additives and color additives used in food.

Naturally Occurring Food Toxins

Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration FDA and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions.

Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins.

Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable.

Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States.

Historically, we have learned that everything is toxic; it is only the dose that separates the toxic from the non-toxic. Even water is toxic if a large amount 4—5 liters is consumed in a relatively short time 2—3 hours. The pathogenesis of water intoxication includes hyponatremia, followed by cerebral edema, seizures and death. Like water, too much of a good thing such as the antioxidant vitamin A, can have acute toxic effects leading to hepatotoxicity [ 1 ] or chronic high levels can have a pro-oxidant effect [ 2 ].

Something as innocent as licorice, when consumed in large amounts may be harmful. For example, Bannister and associates reported hypokalemia leading to cardiac arrest in a year-old woman who had been eating about 1. Clinically, hypokalemia with alkalosis, cardiac arrhythmias, muscular symptoms together with sodium retention and edema, and severe hypertension are observed.

The syndrome may develop at a level of g licorice per day but gradually abates upon withdrawal of the licorice [ 4 ]. For their part, the regulators can limit amounts of potentially toxic substances allowed in food and in those circumstances where setting limits is not effective and public health policy makers provide the public with sufficient information e.

Labeling requirements by the FDA provide the consumer with helpful information about content of fats, carbohydrate, protein, potential allergens, caloric value, etc.

Because some food toxins cannot be removed from foods and others may be created during processing or cooking, consumption of small quantities of food toxins is unavoidable.

The purpose of this review is to illustrate the potential risks of these toxins when consumed at concentrations normally present in foods and the steps taken by regulators to mitigate exposure where possible.

Although regulatory information from countries other than the United States is included, FDA legislation is emphasized. Readers from other countries are advised to consult regulations for their specific region, because regulations and regulatory practices in other countries may differ from those in the United States.

Foods are regarded as such because they are edible—they cannot be unpalatable or toxic—and; foods must have nutritional, hedonic or satietal value—otherwise there would be no point in consuming them. Therefore, in the absence of a spontaneous change or contamination, the concept of a toxic food per se would seem to be an oxymoron. How then, could a food be toxic and still be considered a food—there are two principal means: 1 an ordinarily non-toxic food has become toxic, if even for a small subpopulation; and 2 over-consumption of an ordinarily non-toxic food.

This shift between toxic and non-toxic or toxic only for a select group has the potential for creating headaches for regulatory agencies charged with protecting the health of the public, but as the reader will see in the following pages, the FDA and other regulatory agencies have created some thoughtful and pragmatic solutions for achieving a balance of acceptable risk and unavoidable circumstances.

The framers are to be congratulated on their realistic approach, but a little interpretation is required. The second clause was more of a political consideration than anything else, as there was some disagreement whether chewing gum was swallowed or expectorated; the swallowers prevailed and chewing gum is regulated as a food.

It has also been ruled by the FDA that proposed dietary supplements which are regulated as a subset of foods meant to be held in the mouth, followed by expectoration, are not dietary supplements, because they are not swallowed. A food shall be deemed to be adulterated— a 1 If it bears or contains any poisonous or deleterious substance which may render it injurious to health; but in case the substance is not an added substance such food shall not be considered adulterated under this clause if the quantity of such substance in such food does not ordinarily render it injurious to health….

This clause simply means that although toxic substances may be present in foods, the food is not adulterated if the amount present in the food is not ordinarily injurious to health. For example, tomatine in tomatoes, psoralens in celery or glycoalkaloids in potatoes are normally present in concentrations that are not harmful; however, in the event these amounts are increased through such processes as breeding, mishandling during harvesting, storage or transportation and become harmful, these foods are then considered to be adulterated.

For food ingredients e. A few potential foods are banned outright by regulation such as the slaughter of companion animals cats, dogs and horses for food, offal and colostrum or those foods whose preparation is regulated by guidelines other than current good manufacturing practices e.

Some naturally sourced substances while present in some foods are banned for addition to food for reasons of safety and include safrole, calamus and coumarin a full list of which may be seen in 21 Code of Federal Regulations CFR For those foods or ingredients with potential for harm, but not addressed by a specific regulation, action level, etc.

That is, the lack of a specific action taken by the FDA or any regulatory agency , for a potentially harmful substance is not a license to market that substance.

Interestingly, there are no fruits or vegetables on any theocratic forbidden list. For example, a genetic variant has been described for cilantro, which is perceived by some people as having an unpleasant soapy taste or rank smell [ 10 ].

Another, better known variant is the ability to taste phenylthiourea also known as phenylthiocarbamide, PTU or PTC [ 11 ]. The ability to taste and smell certain substances may be key to evolutionary survival, as while the alkaloids of many potentially poisonous plants confer a bitter flavor, Goff and Klee have indicated that certain flavors and odors may also provide sensory cues for nutritional value of some plants [ 12 ]. For example, the characteristic odor profile of tomato e.

Persistent or total anosmia also represents a clear safety hazard as the individual could not detect the tell-tale signs of decay or putrefaction of unfit foods. There are some food prohibitions that are medically driven, as the result of genetics or autoimmune disease, as shown in Table 1.

Medically driven food prohibitions compiled from NORD [ 13 ]. The Food Allergen Labeling and Consumer Protection Act of FALCPA , effective January 1, , requires labeling of any product containing these ingredients or a protein derived from one of these offending foods or incidental additives or flavors derived therefrom.

Exceptions are limited to any highly refined oil derived from a major food allergen e. There are also a number of food-drug interactions, the consumption of one interfering with the metabolism of the other, which may result in an enhanced or abated effect of the drug Table 2. Food drug interactions used with permission from Kotsonis and Burdock [ 15 ]. Selenium Se enters the food chain via plant and microorganism conversion of inorganic selenium to organically bound forms [ 16 ].

Selenium toxicity i. The most common symptoms of selenosis are loss of hair, deformity, and loss of nails. Other reported symptoms include increased blood selenium levels, diarrhea, fatigue, a garlic-like odor of the breath and bodily secretions, irritability, peripheral neuropathy, and skin lesions [ 18 ].

Selenium intake levels that cause selenosis have not yet been well defined. Exposure to elemental mercury is relatively rare, although was once an occupational disease of hat manufacturers as elemental mercury was used for the curing of animal pelts. Of interest to food toxicology, is the methyl derivative, methyl mercury, formed by bacterial action in an aquatic environment from anthropogenic and natural sources of elemental mercury.

Anthropogenic sources include burning of coal which contains mercury , chloralkali process and other sources of elemental mercury into aquatic environments. In the case of Minamata, Japan, there was a direct discharge of methyl mercury into the environment. Methyl mercury exposure may cause neurological paresthesias, ataxia, dysarthria, hearing defects and death. Developmental delays have been documented in children borne of mothers exposed to methyl mercury [ 21 ].

Other than direct exposure to methyl mercury, exposure usually comes about as the result of methyl mercury becoming incorporated into the food chain, moving up as each predator consumes the smaller and less fortunate animal. Near the peak of the food chain, methyl mercury becomes concentrated in fish including, bonito Sarda spp.

The selection of these species was based on historical data on levels of methyl mercury found in fish consumed in the U. The selection was also based on an FDA action level of 1. Thujone, a monoterpene ketone, is the primary constituent of essential oils derived from a variety of plants, including sage Salvia officinalis , clary Salvia sclarea , tansy Tanacetum vulgare , wormwood Artemisia spp.

Essential oils from these plants are used in herbal medicines, as flavorings in alcoholic drinks and fragrances throughout the world. Thujone is potentially toxic and the presence of alpha- or beta-thujone in food and beverages is regulated by law in several countries. In the US, thujone as an isolated substance is banned as an ingredient to be added to food and many of the natural thujone-containing plant oils e.

Absinthe made from wormwood contains significant levels of thujone and is available in Spain, Denmark and Portugal. Wormwood itself is a popular flavoring for vodka in Sweden, while vermouth, chartreuse, and Benedictine all contain small levels of thujone [ 26 ].

Both alpha- and beta-thujone act as noncompetitive blockers of the gamma-aminobutyric acid GABA -gated chloride channel [ 29 ]. The essential oils of sage, hyssop Hyssopus officinalis L. Thujone is believed to be the toxic agent in absinthism, a syndrome produced by the chronic use of absinthe, made from the essence of wormwood. The syndrome is characterized by addiction, hyperexcitability and hallucinations.

The debilitating illnesses suffered by Vincent Van Gogh and Henri de Toulouse-Lautrec have been linked to absinthism, while the toxicity of thujone was a major factor in banning absinthe in the early s [ 31 ].

A published case report detailed a male subject that drank about 10 mL of essential oil of wormwood believing it was absinthe and became agitated, incoherent and disoriented, subsequently developing renal failure [ 32 ].

Detoxification of thujone is thought to occur via CYPdependent oxidation and subsequent glucuronidation and excretion [ 33 ]. Prussic acid also known as hydrocyanic acid, hydrogen cyanide, or cyanide is formed when cyanogenic glycosides found in leaves, cherry, apple and peach pits, oak moss and other plant tissues are damaged and come into contact with beta -glycosidase or emulsion enzymes. The mucous membranes and blood are bright red as they are oxygenated, but the cells in the tissues cannot utilize the oxygen.

Many fruit trees contain prussic acid glycosides in the leaves and seeds, but only negligible levels are present in the fleshy parts of the fruit [ 35 ].

Prussic acid as found in flavoring ingredients is limited to 25 ppm in cherry pits Prunus avium L. Batsch 21 CFR Batsch must be prussic acid free 21 CFR There are no FDA regulations or guidelines restricting the presence of prussic acid in apple seed Malus spp. The major active antidepressive constituents in St. The mechanism of action is not fully understood, but may involve inhibition of serotonin 5-HT reuptake, similar to conventional antidepressive drugs.

In this manner, hyperforin and hypericin taken in conjunction with other serotonin reuptake inhibitors may contribute to serotonin syndrome , a potentially life-threatening elevation of serotonin in the central nervous system. Hyperforin is also known to induce cytochrome P enzymes CYP3A4 and CYP2C9, which can lead to increased metabolism of certain drugs and decreased clinical response [ 39 ].

In large doses, St. In humans, consumption of St. The FDA limits exposure to St. Johns wort Hypericum perforatum , including the leaves, flowers, and caulis, by mandating that only hypericin-free alcohol distillate form may be used and then, only in alcoholic beverages 21 CFR Certain raw foods have been found to contain substances that suppress the function of the thyroid gland by interfering with the uptake of iodine, an essential nutrient in growth, cognitive function, and hormonal balance.

A lack of functional iodine is known to result in cognitive deficiencies e. The decrease in iodine uptake causes the thyroid gland to enlarge, forming a goiter. Foods that have been identified as goitrogenic include spinach, cassava, peanuts, soybeans, strawberries, sweet potatoes, peaches, pears, and vegetables in the Brassica genus, which include broccoli, brussels sprouts, cabbage, canola, cauliflower, mustard greens, radishes, and rapeseed [ 42 ]. Goiter has also been attributed to the consumption of large quantities of uncooked kale or cabbage.

High temperatures i. Cassava Manihot esculenta is an essential dietary source of energy in the tropics, but contains high levels of linamarin, a glucosinolate.

Cassava must be properly processed-dried, soaked in water or baked to effectively reduce the linamarin content [ 43 ]. Glucosinolates are sulfur-containing substances that are metabolized in the body by thioglucosidase to form thiocyanate, isothiocyanate, nitriles and sulfur.

NUTRIENT TOXICOLOGY

When you miss class it is your responsibility to contact me or find out what you missed. The best food source of these nutrients is protein, but it is important to recognize that not all proteins have equal nutritional value. Parts per trillion, as Timu said. This is quick and simple! Whenever we cook food, we are acting as organic chemists. The latest news stories on chemistry, biochemistry, polymers, materials science from Phys.

Food Chemistry Ppt

The Food Safety and Standard therapeutic. Nutraceuticals: Efficacy, Safety and Toxicity brings together all current knowledge regarding nutraceuticals and their potential toxic effects as written by the scientists at the forefront of their study. Skilled Intake Clinical Assessment pdf Download. Nutraceuticals Coverage is subject to underwriting and the terms, conditions, and limits of the issued policy.

What to know about cassava: Nutrition and toxicity

Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration FDA and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins.

Nutrition is the biochemical and physiological process by which an organism uses food to support its life. It includes ingestion , absorption , assimilation , biosynthesis , catabolism and excretion. The science that studies the physiological process of nutrition is called nutritional science also nutrition science.


Food and Nutritional Toxicology provides a broad overview of the chemicals in food that have the potential to produce adverse health effects. The book covers.


Nutritional Toxicology, Volume I is a sample result that has risen from the need for increased toxicological awareness and understanding by nutritionists and other professionals concerned with food production, utilization, and health. This book aims to collate significant information regarding nutrition-associated toxicity problems. The book is divided into 13 chapters. The first two chapters deal with a general overview of nutritional toxicology.

An Overview of Food and Nutritional Toxicology. In essence, toxicology is the science of poisons, toxicants, or toxins. A poison, toxicant, or toxin is a substance capable of causing harm when administered to an organism. The substances toxicologists study are usually chemical compounds but may be elemental or complex materials. Radioactive elements, heavy metals e.

1 comments

Fauna R.

Food and Nutritional Toxicology provides a broad overview of the chemicals in food that have the potential to produce adverse health effects.

REPLY

Leave a comment

it’s easy to post a comment

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>