Disparities of Selected Metal Levels in the Blood and Scalp Hair of Ischemia Heart Disease Patients and Healthy Subjects

Imbalances in the concentrations of trace metals have become an increasingly recognized source of infirmity worldwide particularly in the development of ischemia heart disease (IHD). Present study is intended to analyze the concentrations of Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn in the blood and scalp hair of the patients and counterpart controls by flame atomic absorption spectrometry after wet-acid digestion. On the average, Cd, Co, Cr, Fe, K, Li, Mn, Na, and Pb revealed significantly elevated concentrations in the blood of the patients compared with the controls (p < 0.05), whereas mean levels of Ca, Cd, Fe, K, Li, Pb, and Sr in the scalp hair were significantly higher in the patients than the controls (p < 0.05). Most of the metals exhibited noticeable disparities in their concentrations based on gender, abode, dietary/smoking habits, and occupations of both donor groups. The correlation study and multivariate statistical analyses revealed some significantly divergent associations and apportionment of the metals in both donor groups. Overall, comparative variations of the metal contents in blood/scalp hair of the patients were significantly different than the controls; thus, evaluation of trace metals status may be indicative of pathological disorders, such as IHD.     

Comparative Assessment of Selected Metals in the Scalp Hair and Nails of Lung Cancer Patients and Controls

Lung cancer is seriously threatening human health and exposure to trace metals is the most important aetiology for lung cancer. Selected essential/toxic metals (Ca, Mg, Na, K, Fe, Zn, Cu, Sr, Li, Co, Mn, Ni, Cr, Cd and Pb) are measured in the scalp hair and nails of lung cancer patients and controls by atomic absorption spectrophotometric method employing nitric acid-perchloric acid-based wet digestion. Average concentrations of Pb, Cd, Mn, Co and Cu are found to be significantly higher (p?<?0.05) in the scalp hair and nails of lung cancer patients compared with the controls, however, appreciably higher concentrations of Zn, Ca, Na, Mg and Cr are noted in the scalp hair of the controls. Most of the metal levels reveal higher dispersion and asymmetry in the scalp hair/nails of the patients compared with the controls. Average metal levels are also compared to investigate probable differences based on sex, abode, food and smoking habits. The correlation study shows significantly diverse mutual variations of the metals in the scalp hair and nails of the patients and controls. Considerable variations in the metal levels are also noted for various stages and types of lung cancer (adenocarcinoma, squamous cell carcinoma, large cell carcinoma and small cell lung cancer). Multivariate apportionment of the metals in the scalp hair and nails of the patients and controls are also significantly diverse. The study reveals considerably divergent variations in the metal levels in lung cancer patients in comparison with healthy subjects.     

Chemometric Evaluation of Elemental Imbalances in the Scalp Hair of Valvular Heart Disease Patients in Comparison with Healthy Donors

The present study deals with the plausible association between the trace elemental imbalances and the emergence of valvular heart disease (VHD). A total of 14 elements including Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr and Zn in the scalp hair of VHD patients and healthy donors were analysed by flame atomic absorption spectrophometry employing wet acid digestion methodology. Median levels of Cu, Fe, Mg, Mn and Sr in the scalp hair of patients were significantly higher compared to those of the healthy donors, while the median concentrations of K and Na were found to be considerably higher in the scalp hair of the healthy donors. In addition, substantially elevated Cu/Zn value in patients indicated the prevalence of inflammatory processes inside the body. The correlation coefficients among the elements in the hair of VHD patients were significantly diverse compared to those of the healthy donors. Multivariate statistical methods showed noticeably dissimilar apportionment of the elements in the two groups. Variations in the elemental levels were also observed with gender, habitat, dietary/smoking habits and occupations of both donor groups. Overall, the study revealed significant imbalances among the essential and toxic elements in the scalp hair of VHD patients compared to those of the healthy subjects.     

Determination of Select Trace Elements in Hair of College Students in Jinzhou, China

Select trace elements (Fe, Cu, Zn, Al, K, Na, Ba, Sb, Pb, As) were determined by ICP-AES after nitric acid-perchloric acid wet digestion in samples of scalp hair of University students. Some metal-to-metal intercorrelations were found. The more often the hair was dyed and marcelled, the higher were the contents of iron, copper, potassium, sodium, barium, lead, and arsenic. Copper levels increased with the degree of myopia, while zinc, lead, aluminum, iron, and potassium decreased with the myopic degree. Copper, zinc, iron, and arsenic levels were lower in white hair, while sodium and lead were higher. The levels of the elements were generally higher in the hair samples of students who drink and smoke. The hair metal contents were found to be influenced by alcohol use and smoking. Hair element analyses thus could be used as noninvasive means of detecting unhealthy lifestyles in college students.     

Characterization of Pb and Cd contamination in the feces and feathers of rook (Corvus frugilegus) and the scalp hair of residents in Qiqihar,northeastern China

The concentrations of Pb and Cd, and trace elements (Cu and Zn) in the urban topsoil, rook (Corvus frugilegus) feces and feathers and human scalp hair were analyzed to examine the potential ecological risk posed by Pb and Cd on local residents of Qiqihar City, northeastern China. Results revealed that the Cd concentrations in the topsoil were ranged from 0.14 to 3.55 mg kg^?1 dry weight (dw). The maximal geoaccumulation indices [a value from logarithmic (a measured metal content/1.5 × background content of the metal in this region), introduced by Muller] of Cd exceeded 3.5, which suggested that this region was seriously contaminated by Cd. The corresponding average detectable concentrations in C. frugilegus feathers and feces were 1.38 and 3.97 mg kg^?1 dw for Pb and 1.04 and 0.69 mg kg^?1 dw for Cd. High Pb and Cd concentrations, respectively, ranging from 7.46 to 24.9 mg kg^?1 dw and from 0.35 to 0.92 mg kg^?1 dw were also detected in the human scalp hair samples. These high Pb and Cd concentrations in C. frugilegus and local people were possibly associated with local industrial wastes and vehicle exhausts. The external tissues (feces and feather) of the rook species can be considered as an indicator of potential Cd toxic risk in this species; however, the human scalp hair is not a reliable biomarker for risk of Pb and Cd in the human being. Effective measures should be established to reduce the inputs of Pb and Cd into the urban environment and to protect the health of local people.     

Interaction Between Zinc, Cadmium, and Lead in Scalp Hair Samples of Pakistani and Irish Smokers Rheumatoid Arthritis Subjects in Relation to Controls

The incidence of rheumatoid arthritis (RA) has been associated with cigarette smoking. The aim of our study was to assess the trace essential and toxic metals, cadmium (Cd), lead (Pb), and zinc (Zn), in scalp hair samples of 32 Irish and 46 Pakistani smokers and non-smokers RA male patients with age range 42-56 years. For comparison purpose, the scalp hair samples of 27 Irish and 55 Pakistani non-RA male subjects of the same age group were collected. The concentrations of trace and toxic elements were measured by inductive coupled plasma atomic emission spectrophotometer and atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials and using conventional wet acid digestion method on the same certified reference materials (CRMs). The recovery of all studied elements was found to be in the range of 97.5-99.7% of certified reference values of CRMs. The results of this study showed that the mean values of Cd and Pb were significantly higher in scalp hair samples of both smoker and non-smoker RA patients than in referents (P < 0.001), whereas the concentration of Zn was lower in the scalp hair samples of smokers and non-smokers rheumatoid arthritis patients. The deficiency of Zn and the high exposure of Cd and Pb as a result of cigarette smoking may be synergistic risk factors associated with rheumatoid arthritis.     

Essential trace and toxic element distribution in the scalp hair of Pakistani myocardial infarction patients and controls

The pathogenesis of heart disease has been associated with changes in the balance of certain trace elements. The aim of this study was to evaluate the Zn, Fe, Cu, Cr, Ni, Pb, and Cd contents in scalp hair samples of myocardial infarction (MCI) patients hospitalized in the cardiac ward of National Hospital in Hyderabad city (Pakistan). Scalp hair samples were collected from 193 patients (104 male, 89 female) of 3 age groups (46–60, 61–75, and 76–90 yr), for a comparative study, 200 normal, healthy subjects (103 male, 97 female) of the same age groups residing in the same city were selected. All metals in scalp hair samples were assessed by a flame/graphite furnace atomic absorption spectrophotometer, prior to microwave-assisted and conventional wet acid digestion methods. Results were calculated in micrograms per gram. The mean values of Fe and Zn of scalp hair samples of MCI patients were significantly reduced compared to the control subjects of both genders. The mean Fe concentrations in male patients were 19.42, 12.36, and 6.98 vs 30.69, 24.42, and 16.75 for the control patients in the three age groups (46–60, 61–75, and 76–90 yrs, respectively). The mean Zn concentration in male patients were 169.2, 149.4, and 107.7 μg/g vs 206.1, 188.0, and 154.4 μg/g for the control group (p<0.002, 0.004, and 0.001) in all three age groups, respectively. These differences were also observed in the female study groups. The mean values of Pb, Cd, and Ni were significantly high in patients compared to healthy subjects (mean Pb in male patients: 11.85, 12.89, and 14.52 those of female patients were 11.88, 12.73, and 14.21 vs the male controls patients (6.08, 7.56, and 8.56) and female controls (5.99, 7.41, and 8.25) for all three age groups, respectively. The concentration of Ni and Cd in the scalp hair samples of the heart patients of both sexes were significantly higher compared to the control; in the case of Ni the range of significant difference for males was found to be p<0.001–0.009 and for females to be p<0.0.002–0.007 and significantly high concentration of Cd were observed in hair samples of patients than in controls in the range for males (p<0.001–0.009) and in females (p<0.001–0.011). The Zn/Cu and Zn/Cd ratios in the scalp hair (p<0.01) of the diseased groups were significantly lower than that of the healthy groups. Deficiency of essential trace metals and high level of toxic metals might play a role in the development of heart disease in the subjects of this study. Toxic metals might also cause diminished absorption of essential elements.     

The exposure level of heavy metals at four different locations near Gan-Ning-Meng reaches of the Yellow River,China

Hair, water, and sediment samples (n = 69, 27, and 24, respectively) were collected at four locations (P1–P4) along the Yellow River Gan-Ning-Meng (GNM) reaches, China. Total elemental contents of Cd, Cr, Cu, Fe, Mn, Pb, and Zn were determined using inductively coupled plasma mass spectroscopy (ICP-MS) to investigate their distribution and exposure levels in the different media. Results showed that trace metals had widely spatial variability in water and hair samples. There were the highest levels of mean concentrations of Cd, Cu, Fe, Mn, Pb, and Zn (geometric mean, GM = 0.22, 17, 65, 3.0, 4.9, and 170 μg/g, respectively) in residents' hairs living at P2. Most of the hair donors in this study showed high concentrations of Cr when compared with the literature. Differences could be distinguished for Mn (p = 0.001) and Fe (p = 0.001) with gender, and for Cr (p = 0.021), Zn (p = 0.003), and Pb (p = 0.035) with age, respectively. The pollution assessments revealed an unpolluted degree in filtered water and a moderately polluted degree for Cd in sediments at P1–P4. Correlation analysis showed significant correlations between hair and sediment samples for Cr and Mn. This paper provides basic and useful information in facing public and environmental health challenges in the GNM sections of the Yellow River.     

Health risk assessment of heavy metals via dietary intake of wheat in Golestan Province,Iran

Concentration of five heavy metals including lead (Pb), cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in wheat collected from silages of Golestan Province, Iran, was determined using atomic absorption spectroscopy. Dry ashing method was applied for precise determination of the five heavy metal contents. The concentrations of heavy metals were recorded as the following: Pb (0.013–0.14), Cd (0.008–0.031) by graphite furnace method and Cu (0.48–6.2), Fe (58.50–406.9), and Zn (3.41–32.75) by flame method, all in mg.kg^?1. The mean concentration of all the aforementioned heavy metals was (0.057 ± 0.003), (0.016 ± 0.005), (2.7 ± 0.17), (111.2 ± 21), and (5.7 ± 0.22) mg.kg^?1, respectively. The level of heavy metals decreased in the order of Fe>Zn>Cu>Pb > Cd. Highest amount was related to Fe and the lowest amount to Cd. Concentrations of heavy metals in all the wheat samples were below the permissible limits set by the Food and Agriculture Organization/World Health Organization and Iranian National Standard Organization and did not pose any threat to the health of consumers.     

Roadside Topsoil Concentrations of Lead and Other Heavy Metals in Ibadan,Nigeria

Concentrations of Pb, Zn, Cd, Cu, Cr, Co, and Ni were determined in roadside topsoil collected from locations of varied vehicular traffic densities in the city of Ibadan, Nigeria, with a view to determining the level of contamination and the contribution of traffic density. Levels of Pb, Zn, Cd, and Cu were elevated above background concentrations measured in control areas. Average values (ppm) for all sample locations were Pb — 81±140; Zn — 48±37; Cd — 0.55±0.49; Cu — 17±17; Cr — 22.1±9.6; Co — 7.9±3.8; Ni — 10.5±9.7. Factors of accumulation of metals in roadsides relative to control sites were highest for Pb. Vehicular traffic was not an important source of chromium, cobalt and nickel, for which roadside concentrations were about those of the control sites. Metal concentrations were poorly correlated with traffic volumes. An average of about 60% of total soil concentration of the metals were determined to be held in bioavailable geochemical phases, of which the highest concentrations were mostly held in either the reducible or oxidizable phase. Levels of the metals in the topsoil were generally lower than the soil quality criteria of some developed countries.     

Relationships Between Metal Concentrations in Human Hair and in Soil,Road Dust,and Rice

The relationships between metal contents in soil, road dust, and rice, and in human hair from a rural area of China were observed for Cr, Cu, Mn, Ni, Pb, and Zn. The results showed that the mean concentrations of Mn in human hair were higher than the highest reference value. The concentrations of Cr, Cu, Ni, and Zn in soil and road dust were usually higher than their background values. The enrichment factors indicated that the determined metals in soil and road dust were usually derived from natural sources. Chromium, Pb, and Zn in soils and road dusts from several sites were slightly influenced by anthropogenic sources. The regression analyses showed that positive relationships usually exist between the concentrations of the determined metals in rice and in human hair as well as in soil and in human hair. However, relationships between metal concentrations in road dust and in human hair were less obvious. The study demonstrated that human hair was an applicable biomonitor of metal concentrations in rice, soil, and road dust from a rural area in China. Metal concentrations in local human hair could be used to predict contamination levels of metals in rice and soil.     

Evaluation of Cadmium, Chromium, Nickel, and Zinc in Biological Samples of Psoriasis Patients Living in Pakistani Cement Factory Area

Psoriasis is a noncontiguous common and chronic skin disorder. The aim of the present study was to compare the level of trace elements cadmium (Cd), chromium (Cr), Nickel (Ni), and zinc (Zn) in biological samples (whole blood, urine, and scalp hair) of psoriasis patients of both gender age ranged (25–55 years) at mild, moderate severe, and more severe stage (n?=?418) living in the vicinity of cement factory. For comparison purposes, healthy age-matched referent subjects, residents of industrial and non-industrial area, of both gender were also selected (n?=?241). The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of methodology was checked by using certified reference materials (CRMs) and conventional wet acid digestion method on same CRMs and real samples. The results of this study showed that the mean values of Cd, Cr, Ni, and Pb were significantly higher in scalp hair, blood, and urine samples of mild and severe psoriasis patients as compared to referents (p?<?0.001), while the concentration of Zn was lower in the scalp hair and blood, but higher in the urine samples of psoriasis patients. The deficiency of Zn in psoriasis patients may be undoubtedly caused by the toxic element exposures via cement factory.     

Risk Element (As,Cd, Cu,Pb, and Zn) Contamination of Soils and Edible Vegetables in the Vicinity of Guixi Smelter,South China

Risk element (As, Cd, Cu, Pb, and Zn) contamination in soils and in two edible vegetables (Solanum melongena L. and Capsicum annum L.) was investigated in the vicinity of Guixi Smelter, South China. Soil As concentrations averaged 23.9 mg/kg. Sites near the smelter tailings recorded the highest levels of As and heavy metals in soils. The concentration order of heavy metals in soils was Cd < Pb < Zn < Cu. Cu and Cd in soils were abundant in the exchangeable and bound to carbonate fraction, while Pb and Zn were in the residual fraction, limiting their potential toxicity as pollutants. The proportions of the metals in the mobile fraction followed the order Pb < Zn < Cu < Cd. In Solanum melongena L. and Capsicum annum L., Zn concentration was the highest, followed by Cu, Cd, and Pb, different from that in soils and in the mobile fraction. Concentrations of heavy metals in the labile fractions in soils and in vegetables presented significant correlation (p < 0.05). Both of the two vegetables are not the Cu and Zn accumulators. As for Cd and As, Capsicum annum L. poses a higher risk to animal and human health than Solanum melongena L., with soil-plant transfer coefficients more than three. Root-stem is the main barrier for most of the heavy metals and As in the two vegetables, resulting in higher metal concentrations in roots relative to other plant tissues. The low stem-fruit transfer coefficients for Zn in Solanum melongena L. and for Pb in Capsicum annum L. suggested that very few of them could reach the fruits.     

Cadmium, Lead, Copper and Zinc in Breast Milk in Poland

Mother's milk is the fundamental food for infants. It contains proteins, fat, carbohydrates and essential metals which are necessary to ensure correct functioning of the organism. Unfortunately, breast milk is a potential source of toxic metals, which are dangerous for a baby. In Poland, previous research concerning the content of metals in breast milk was very scarce or its results were unavailable. The present study aimed at assessing the content of Cd, Pb, Cu and Zn in human breast milk, as well as estimating the mean weekly intake of these metals by breast-fed infants from Poland. The average concentrations of Cd, Pb, Cu and Zn were 2.114 μg/l, 6.331 μg/l, 0.137 mg/l and 1.623 mg/l, respectively. The admissible levels of supply of these toxic metals has not been exceeded, but their contents were high, particularly in 6-month-old infants (nearly 85 % TWI for Cd and nearly 70 % BMDL₀₁ for Pb). The daily intake of Cu and Zn did not fully satisfy the infant's requirements determined by Polish standards and WHO recommendations. Since the lifestyle of lactating women has a direct influence on the content of these elements in breast milk, women should be educated in this respect with particular focus on eliminating tobacco smoking, both by breastfeeding mothers and by their direct environment.     

Heavy metal contamination and health risks of indoor dust around Xinqiao Mining Area,Tongling, China

Abstract

In this study, the concentrations and health risks of heavy metals (Cu, Pb, Zn, Ni, Co, Cd, and Cr) in indoor dust are investigated in the vicinity of the Xinqiao mining area, Tongling, China. Results indicate that heavy metals except Co were clearly enriched in indoor dust. Especially Cd was extremely enriched, followed by Zn, Cu, and Pb. However, no significant regional differences (p?>?0.05) were found in other elemental contents aside from Cu. Statistical analysis revealed that metal elements except Co were presumed to originate primarily from mining activities. Health risk assessment indicated that the hazard quotients and hazard indices of all studied metal elements were less than 1 and thus posed no potential noncancer health risks to adults and children. Moreover, the cancer risks of Ni, Cr, Cd, and Co were within acceptable ranges, implying no cancer risk to local residents; however, the noncarcinogenic risk of Pb and the carcinogenic risk of Cr and Cd warrant close attention.     

Lead and cadmium in the hair and blood of children from a highly industrial area in Poland

The study covered the children living in Miasteczko ?lcaskie, near the largest Zn plant in Poland. This is one of the areas highly contaminated with heavy metals. The subjects were 158 children aged from 8 to 15 (98 boys and 60 girls). The average Pb and Cd levels in the hair of the entire children population was 8.21 ± 5.59 μg/g, and 0.91 ± 0.61 μg/g, and the average Pb and Cd levels in their blood were 14.32 ± 3.98 and 0.52 ± 0.24 μg/dL^-1, respectively. The children population under investigation was divided according to their sex. The hair of the girls contained, on the average, 5.06 ± 2.81 μg/g of Pb and 0.74 ± 0.48 ug/g of Cd and the hair of the boys 10.14 ± 6.0 μg/g of Pb and 1.01 ± 0.65 ug/g of Cd. The blood of the girls contained, on the average, 13.23 ± 4.23 μg/dL of Pb and 0.48 ± 0.21 μg/dL of Cd, and the blood of the boys 14.99 ± 3.68 μg/dL of Pb and 0.55 ± 0.24 μg/dL of Cd. Thus, both the hair and blood of the boys accumulated more Pb and Cd than those of the girls. A correlation between the concentrations of these metals was confirmed.     

Fractionation and ecological risk assessment of trace metals in surface sediment from the Huaihe River,Anhui, China

Abstract

The Huaihe River has suffered increasing pressure from pollutants including metals from anthropogenic activities. In this study, enrichment and fractionation behavior of trace metals were analyzed in sediment samples obtained from fish spawning area of the Huaihe River (Anhui Section) to evaluate the potential ecological risk of trace metals to aquatic organisms. Geochemical indices including enrichment factor and geo-accumulation index as well as mean probable effect concentration quotient and risk assessment code were adopted to assess the contamination degree and potential ecological toxicity. Results showed that the total contents of Cu, Pb, Zn, Cr, Cd, As, and Hg in sediment were 23.1?±?6.4, 32.3?±?11.1, 76.8?±?14.2, 84.6?±?17.2, 0.2?±?0.1, 9.0?±?3.0, and 0.031?±?0.010?mg/kg, respectively. The indexes EF and I_geo revealed slight accumulation for Pb, Zn, Cr, Cd, and As in some sampling sites. The result of Q_m-PEC demonstrated that trace metals in sediment were not toxic to aquatic organisms. Most trace metals appeared to mainly associate with the residual form suggesting lower mobility whereas Cd presented a relative higher exchangeable fraction indicating a great degree of bioavailability. The result of risk assessment code (RAC) evaluation revealed that Cd poses a medium ecological risk for aquatic organisms whereas most of the other trace metals pose low risks.     

The first insight into the trace element status of human adrenal gland accompanied by elemental alterations in adrenal adenomas

BackgroundThe baseline status of trace metals in adrenal tissue is unresolved, while the elemental profile for any adrenal pathology has not been examined so far. This study aimed to determine the baseline status of important toxic (Ni, As, Cd, Pb, Th, U) and essential trace elements (Mn, Co, Cu, Zn, Se) in healthy adrenal tissues (HATs) as well as to examine whether there are alterations in the elemental composition of adenomatous adrenal tissues (AATs). Furthermore, this study aimed to find potential trace metals that could play a role in the pathogenesis of adrenal adenoma (AA).MethodsThe study included 45 patients diagnosed with AA. Impacts of relevant parameters such as gender, age, smoking habits and nodular sizes were considered. All samples were subjected to microwave digestion and the trace elements were determined by inductively coupled plasma mass spectrometry (ICP-MS).ResultsThis is the first study that provided an insight into the elemental status of HATs. It was also shown that AATs had altered trace metal contents. Compared to HATs, the most significant findings were related to the high content of essential (Cu, Mn, Se, Zn) and Pb as a non-essential metal. Although gender, age and smoking habits had a modest effect on metal profiles, the most significant alterations were related to the nodular diameter above 4 cm, indicating that the growth of benign tumor could influence changes in elemental composition.ConclusionFor the first time the baseline contents of essential and toxic trace metals in HATs were determined. The results of this study may highlight the role of toxic and essential trace metals in AAs and could provide new insights into the molecular basis of pathophysiological changes caused by the hazardous effects of trace metals on adrenal structure and function.     

Statistical Evaluation of Trace Metals,TSH and T<Subscript>4</Subscript> in Blood Serum of Thyroid Disease Patients in Comparison with Controls

The present study is based on the measurement of concentrations of selected trace metals (Fe, Zn, Cu, Co, Mn, Ni, Cr, Cd and Pb) and thyroid hormones (TSH and T₄) in blood serum of hypothyroid and hyperthyroid patients in comparison with healthy donors/controls in order to establish the imbalances of the trace metals in diseased subjects. The serum samples were digested in HNO₃-HClO₄ mixture and quantification of the metals was performed by flame atomic absorption spectrometry. Average levels of Fe, Ni, Cu, Cr, Pb and TSH were found to be significantly higher (p < 0.05) in the serum of hypothyroid patients compared with other donor categories, while mean concentrations of Mn, Cd and T₄ were significantly elevated in the serum of hyperthyroid patients compared with other donor groups (p < 0.05). The correlation pattern of trace metals in the serum of patient groups revealed significantly different mutual associations compared with the controls. PCA and CA pointed out the interferences of the toxic metals with essential metals in the serum of both patient groups compared with the controls. Most of the metals exhibited noticeable disparities in their concentrations based on gender, food habits and tobacco use for all donor groups. Thus, the pathogenesis of thyroid diseases is significantly affecting the essential trace and toxic metals balance in both patients groups.     

Heavy metal pollution monitoring using the brown seaweed Padina durvillaei in the coastal zone of the Santa Rosalía mining region, Baja California Peninsula, Mexico

The coastal marine sediments near Santa Rosalía on the eastern coast of the Baja California Peninsula (Mexico) are heavily polluted by metals due to copper mining and smelting over the past century (up to 1984). The present study compares the accumulation of metals in the brown seaweed Padina durvillaei from the central segment of the coast of Santa Rosalía (polluted by Co, Cu, Mn and Zn) and from two segments north and south of the known “hot spot”. The seaweed samples were collected in May and August 2004 and June 2005 at 13 stations located along the Santa Rosalía mining region. Heavy metal concentrations were measured by instrumental neutron activation analysis (Co and Fe) directly in dried homogenized subsamples or by flame atomic absorption spectrophotometry (Cd, Cu, Mn, Ni, Pb and Zn) after complete strong acid digestion of sub-samples. The means and standard deviations of the concentrations in dry tissues of Padina durvillaei specimens for all the studied metals and stations lie in the following sequence: Cd (3.6 ± 1.6 mg kg⁻¹) < Co (6.5 ± 6.1 mg kg⁻¹) < Pb (7.8 ± 6.2) < Ni (9.96 ± 5.28 mg kg⁻¹) < Cu (53 ± 38 mg kg⁻¹) < Zn (63 ± 43 mg kg⁻¹) < Mn (295 ± 269 mg kg⁻¹) < Fe (2243 ± 2325 mg kg⁻¹). This increase of the average concentrations was statistically significant. Principal Component Analysis showed that Factor 1 (36.46%) displays high positive loadings for Co, Cu, Mn and Zn, reflecting the influence of local anthropogenic pollution on the seaweed composition, while Factor 2 (26.91%) is important for Co, Fe and Ni and probably corresponds to the adsorption or accumulation of terrigenous elements of the regional origin, while Factor 3, with a high positive loading for Pb and a high negative loading for Cd, is probably controlled by local and regional anthropogenic input of Pb and episodic supply of Cd by local upwellings. The results of ANOVA for each element do not show any significant differences between the average concentrations for Cd, Fe, Ni and Pb in the seaweed of the three segments, or between the central and southern segments for Cu, Mn and Zn. Cobalt contents in the seaweed from the northern and central segments are, however, significantly different from the southern segment. This indicates that element concentrations in Padina durvillaei generally do not follow the drastic increases and gradients of Cu, Co, Mn and Zn contents detected in surface sediments. The apparent contradiction could be explained by a low geochemical mobility of these metals in the polluted sediments, composed mainly of stable residues of smelter wastes, with very low content of organic matter usually driving diagenetic mobilization of some metals into interstitial waters and then to the overlying water.