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At least 19 recordsLinked to original sources
PubMed1977

Nutritional factors in relation to heavy metal toxicants.

An increased environmental exposure to various toxic heavy metals such as lead, cadmium, or mercury seems to be a fact of 20th-century life. But relatively little attention has been paid to the possible implications of sucy exposure for the nutritional status of humans and animals. This review summarizes the information available concerning the effect of various nutritional factors in resistance to metal toxicants and the effect of heavy metal toxicity on nutritional status. In particular, the following questions are considered: 1) Are there any examples of heavy metal toxicity that are potentiated by a nutritional deficiency? 2) Is there any evidence that nutritional deficiency can be caused by heavy metal toxicity? 3) Is there any proof that heavy metal toxicity can be decreased by an excess intake of nutrients: 4) Is there any proof that heavy metal toxicity can be increased by an excess intake of nutrients? The discussion is focused primarily on studies with animal models but, wherever possible, implications for human health are pointed out.

Animals↗
PubMed1978

Neurological syndromes produced by some toxic metals encountered industrially or environmentally.

Toxic metals encountered industrially or environmentally may produce the following syndromes: 1) Peripheral neuropathy: which is mainly sensory in arsenic and entirely motor with inorganic lead, organophosphorus compounds and tallium produce a mixed form of peripheral neuropathy. 2) Encephalopathy: usually with lead poisoning where ataxia and hemiplegia or optic atrophy may occur. 3) Optic neuritis: transient or permanent impairment of vision in arsenic poisoning and blurring of vision followed by field fedects with thallium poisoning. 4) Cerebellar disturbances: in the form of ataxia in organic mercury. 5) Parkinsonism: extrapyramidal signs occurs in manganese poisoning shown as mask face and rigidity of muscles. 6) Mental changes: as acute psychosis in organic lead and erethism in organic mercury.

Adult↗
PubMed1978

The role of hypersensitivity and the immune response in influencing susceptibility to metal toxicity.

The immune status of the individual is an additional variable which has to be taken into account in any consideration of factors which influence the metabolism and toxicity of metals. The commonly occurring phenomena are described resulting from increased cellular reactivity to platinum, mercury, gold, nickel, chromium, and beryllium, and an attempt has attempt has been made to classify these into the four types of immune response. The clinical effects can be very varied, giving rise to conjunctivitis, rhinitis, asthma, urticaria, contact dermatitis, proteinuria, nephrotic syndrome or blood dyscrasia. Of these effects, cutaneous hypersensitivity is the most common, affecting both industrial and general population groups. Metal compounds used in therapeutics and metals used in prostheses have also been responsible for hypersensitive reactions.

Anaphylaxis↗
PubMed2025

The biological relevance of potentially toxic metals in freshwater fish.

Trace elements are essential for a number of physiological functions including oxygen transfer, enzymatic reactions and antioxidant protection of the animal organism. Elevated concentrations outside the physiological optimum, on the other hand, can cause undesirable health complications, disrupt metabolic pathways, reproductive capacity, or oxidative balance. The negative anthropogenic impacts on the environment are alarming and the impacts on the aquatic environment have been increasing disproportionately in recent years. Against this background, all potential threats to biota need to be explained and better understood, the possible risks need to be better informed and understood, and a balance needs to be struck between the fundamental nature and the harmful effects of these metals. This mini-review examines the roles of potentially toxic metals including cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn) in fish physiology. This document also elucidates the mechanisms underlying the assessment of regulatory processes, the potential negative consequences of overexposure, the interactions of these metals on fish health, and in the environmental context.

biomarker↗
PubMed1979

Polarography and voltammetry in studies of toxic metals in man and his environment.

A brief introduction on sources, occurrence and fate of some toxic trace metals found in the natural environment is followed by a discussion of general methodological aspects from the trace chemical viewpoint. The versatile, significant and specific potentialities of advanced polarographic and voltammetric methods are compared with relevant non-electrochemical alternatives. They are subsequently demonstrated by a survey on representative applications, results and findings on problems from all types of environmental compartments and food chains to man, with emphasis on the toxic trace metals Cu, Cd, Hg, Pb, and also in certain matrices for Zn, As, Se, Tl and Bi. A final section is devoted to the particular potentialities of the electrochemical approach for speciation studies in natural waters at realistic trace levels of the dissolved toxic metals, e.g. Zn, Cd and Pb.

Chemical Phenomena↗
PubMed1979

Wet versus dry weights for heavy metal toxicity determinations in duck liver.

Determinations for heavy metals in duck liver using wet weight in lieu of dry weight produced errors that could not be quantitated. Weight loss through air-drying ranged from 10 to 21% in the first 2 h. for frozen tissue and 7 to 11% for fresh tissue. This difference becomes increasingly variable with time.

Animals↗
PubMed1978

Nutritional considerations in designing animal models of metal toxicity in man.

In recent years, exposure of man to increasing amounts of metals has occurred rather generally from industrial contamination and variably from intake of dietary mineral supplements. Adverse effects of individual metals can be markedly altered by dietary levels of other essential and nonessential inorganic elements, essential organic nutrients and other nonessential dietary components. Experimental diets for establishing baseline responses to excess elements should be formulated to meet the animal's requirements only. These reference diets can then be modified to mimic man's average dietary intake as well as meal patterns. Improved animal models should provide better data for assessing hazards of excess metal intake by man.

Aging↗
PubMed1978

Abnormalities in pulmonary function after brief exposure to toxic metal fumes.

A 26-year-old welder became ill after exposure to zinc and cadmium fumes at work. His initial clinical course was consistent with that of metal fume fever, but persistence of symptoms and signs beyond the usual duration in this condition led to suspicion of a toxic pulmonary reaction to cadmium. The finding of high percentages of both metals in the urine confirmed this diagnosis. Pulmonary function tests showed restriction of lung volumes, with increased elastic recoil and reduced diffusion, but no evidence of airways obstruction. Chest roentgenograms indicated central pulmonary edema, which cleared in 6 days. Follow-up assessment 2 years later showed incomplete improvement of the restrictive ventilatory defect.

Adult↗
PubMed1979

Nutritional influences on metal toxicity: cadmium as a model toxic element.

The nutrient quality of the diet has been shown repeatedly to be a significant factor in modifying the response of man and animals to toxic element exposure. Deficiencies of several essential nutrients have been shown to exacerbate the effects of cadmium and supplements of such nutrients have been shown to ameliorate the toxicity. Thus the effects of exposure to a toxic element, such as cadmium, may vary, depending on interactions with other elements which are present in the diet in different concentrations.

Adolescent↗
PubMed1978

Metal toxicity to embryos and larvae of seven freshwater fish species--I. Cadmium.

The embryos and larvae of seven freshwater fish were exposed to low concentrations of cadmium in soft water. All species were killed or their growth retarded by concentrations ranging from about 4 to 12 microgram Cd/liter. The larvae were consistently more sensitive than the embryos. The agreement between these results and those from life-cycle chronic toxicity studies indicates that embryo and larval exposures will give reliable estimates of the chronic toxicity of cadmium to additional fish species. A 60-day exposure period appears to be appropriate for determining larval sensitivity to cadmium.

Animals↗
PubMed1978

Metal toxicity to embryos and larvae of eight species of freshwater fish-II: copper.

Fish larvae and early juveniles of all species tested (brook trout, rainbow trout, brown trout, lake trout, northern pike, white sucker, herring, and smallmouth bass) were more sensitive to copper than the embryos. Embryo survival was affected only at the higher concentrations tested, for all species except the rainbow trout. The concentrations of copper that caused significant effects on the larval standing crop were similar for all species (31.7-43.5 microgram Cu/1) except the northern pike, which seemed to be considerably more resistant (104.1 microgram Cu/1). Copper concentrations shown to have no significant effects on the early developmental stages of these species are considered close estimates of the copper concentrations that would have no measurable adverse effects during a complete life cycle toxicity test under similar test conditions.

Animals↗
PubMed1979

Toxic metals in street and household dusts.

Street and household dusts have been sampled within the Lancaster area (U.K.), and analysed for Pb, Cd, Cr, Co, Cu, Ni and Zn. The concentration of each metal has been determined both as total and extractable metal, the latter referring to metal soluble in a 0.07N hydrochloric acid solution. The results are discussed in relation to the sources of the metals, and possible health hazards to children exposed to the dusts.

Child↗
PubMed1979

Colored gift wrapping papers as a potential source of toxic metals.

Sanitary land fills are the alternate to waste incineration in New Jersey. While industrial waste disposal is controlled, few restrictions apply to the disposal of domestic solid waste. Among the materials of concern from domestic sources are colored gift wrapping papers. Cadmium, chromium, copper, iron, manganese, molybdenum, nickel, lead and zinc were determined in some dozen and a half samples of gift wrapping paper by atomic absorption spectrometry after wet ashing and after simulated leaching. High levels of lead and chromium were found in many of the papers. The leachates showed correspondingly high levels of lead.

Metals↗