OBJECTIVETo determine whether lead affects brainstem auditory evoked potentials (BAEPs) in low-to-moderate lead exposed children.

METHODSBAEPs were recorded from 114 asymptomatic children aged 1 - 6 years. Average values were calculated for peak latency (PL) and amplitude (Amp). Whole blood lead (PbB) levels were assessed by graphite furnace atomic absorption spectroscopy. Based on their PbB levels, subjects were divided into low lead (PbB < 100 micro g/L) and high lead subgroups (PbB > or = 100 micro g/L).

RESULTSThe PbB levels of the 114 subjects ranged from 32.0 to 380.0 micro g/L in a positively skewed distribution. The median of PbB levels was 90.0 micro g/L while the arithmetic average was 88.0 micro g/L. Of the subjects, 43.0% (49/114) had levels equal to or greater than 100 micro g/L. Bilateral PLs I, V, and III of the left ear in the high lead subgroup were significantly longer than those in the low lead subgroup (P < 0.05). A positive correlation was found between PbB levels and bilateral PLs I, V and III of the left ear (P < 0.05), after controlling for age and gender as confounding factors. A significant and positive correlation between PbB levels and PL I of the left ear, even when PbB levels were lower than 100 micro g/L, in the low subgroup (r = 0.295, P = 0.019) was also found.

CONCLUSIONSLead poisoning in children younger than 6 years old is a very serious problem to which close attention should be paid. The indications that lead prolongs partial PLs may imply that lead, even at PbB levels lower than 100 micro g/L, impairs both the peripheral and the central portions of the auditory system. BAEPs may be a sensitive detector of subclinical lead exposure effects on the nervous system in children.

Child ; Child, Preschool ; Evoked Potentials, Auditory, Brain Stem ; drug effects ; Female ; Humans ; Infant ; Lead ; blood ; toxicity ; Lead Poisoning ; physiopathology ; Male

We aimed to investigate the short-term correlation between blood lead levels and oxidative stress generation in coal miners. The study involved 94 male coal miners from the Velenje Coal mine, arranged into four groups: three groups according to the number of consecutive working days, and a fourth control group. Miners who worked for three consecutive days had higher blood levels of lead and 8-isoprostane than the control group (P < 0.001). Correlation between lead and 8-isoprostane was of medium strength (r = 0.512, P < 0.001). Short-term lead environmental exposure can potentially harmful and should be considered when formulating improvements in working processes.
Adult ; Coal Mining ; Environmental Pollutants ; toxicity ; Humans ; Isoprostanes ; blood ; Lead ; blood ; toxicity ; Male ; Occupational Exposure ; Oxidative Stress ; drug effects

OBJECTIVETo explore the effects of lead on the thyroid function of occupationally exposed workers.

METHOD157 workers occupationally exposed to lead in a smelting factory were investigated. The concentration of lead in air at workshop was measured by flame atomic absorption spectrophotometry (FAAS) and the levels of blood lead (PbB) by atomic absorption spectrophotometry (AAS), zinc protoporphyrin (ZPP) by ZnPP meter, as well as the indexes of thyroid function, thyroid-stimulating hormone (TSH), triiodothyronine (T(3)), thyroxin (T(4)), free T(3) (FT(3)), and free T(4) (FT(4)) in serum by radioimmunoassay.

RESULTSThe workers with higher level of blood lead (> 2.88 micro mol/L) showed lower levels of T(3) [(1.54 +/- 0.39) nmol/L] and FT(3) [(5.50 +/- 1.26) pmol/L] than those with lower blood lead level [PbB: (1.92 approximately 2.88) micro mol/L group, T(3): (1.71 +/- 0.45) nmol/L, FT(3): (6.12 +/- 1.64) pmol/L, P < 0.05]. There was no obvious effect of length of service on thyroid hormone of exposed workers.

CONCLUSIONHigher level of blood lead may cause certain damage to thyroid function by inhibiting deiodination of T(4). No obvious relation between length of service and thyroid function was found.

Adult ; Female ; Humans ; Lead ; blood ; toxicity ; Male ; Middle Aged ; Occupational Exposure ; Thyroid Gland ; drug effects ; physiology

Child ; Child, Preschool ; China ; epidemiology ; Data Collection ; Health Policy ; Humans ; Infant ; Infant, Newborn ; Lead ; blood ; toxicity ; Lead Poisoning ; blood ; complications ; epidemiology ; prevention & control ; Risk Factors

OBJECTIVETo estimate the level of blood lead and some haematological parameters in the workers occupationally exposed to lead so as to know the effect of lead exposure on hematopoietic system in exposed workers.

METHODSThe graphite furnace atomic absorption spectrocopy was used to determine blood lead (BPb). The haematological parameters were determined by Sysmex KX-21 automated haematology analyzer.

RESULTSHemoglobin (Hb) in the lead-absorption group[male: (129.3 +/- 12.3) g/L, female: (112.2 +/- 9.4) g/L], and hematocrit (HCT) in the lead-absorption group[male: (0.338 +/- 0.030) L/L, female: (0.302 +/- 0.028) L/L] were significantly lower than those in normal people group and lead-exposed group (P < 0.05, P < 0.01). The relationships between BPb and Hb, HCT were weakly negative correlation. Red cell distribution width (RDW) in the lead-absorption group(male: 16.68% +/- 0.80%, female: 16.98% +/- 0.98%) were significantly higher than those in normal people group and lead exposed group, and RDW in lead exposed group (male: 14.77% +/- 0.83%, female: 14.92% +/- 1.13%) were higher than that in normal people group. BPb was weakly positively correlated with RDW.

CONCLUSIONHb, HCT and RDW were three indices which may reflect the occurrences and degrees of anaemia in lead exposed workers.

Anemia ; chemically induced ; Erythrocytes ; drug effects ; Female ; Hematocrit ; Hemoglobins ; analysis ; Humans ; Lead ; blood ; toxicity ; Male ; Occupational Exposure ; adverse effects

OBJECTIVETo investigate the polymorphism of delta-aminolevulinic acid dehydratase(ALAD) and the genetic susceptibility to lead toxicity in Uighur and Yi population in China.

METHODSThe ALAD genotypes were determined by PCR and MspI restriction fragment length polymorphism techniques in 214 Uighur individuals from Xinjiang autonomous region and 144 Yi individuals from Yunnan province. The correlation between the polymorphism of ALAD and blood lead levels, and the factors affecting the latter were explored.

RESULTSThe frequencies of the allele ALAD1 and ALAD2 in Uighur are 0.91 and 0.09; and in Yi are 0.98 and 0.02 respectively. In Uighur the average blood lead level was (76 +/- 4) microgram/L, and 25.7% individuals with blood lead level > or = 100 micrograms/L. In Yi the average blood lead level was (50 +/- 16) microgram/L, and 6.3% individuals with blood lead level > or = 100 micrograms/L. However, no statistic correlation between the distribution of ALAD alleles and the blood lead level was found in both populations.

CONCLUSIONThe genetic susceptibility of ALAD polymorphism to lead toxicity may exhibit in a lead dose-dependent manner.

China ; ethnology ; Dose-Response Relationship, Drug ; Genetic Predisposition to Disease ; Humans ; Lead ; blood ; toxicity ; Polymorphism, Genetic ; Porphobilinogen Synthase ; genetics

Adult ; Enzyme-Linked Immunosorbent Assay ; Female ; HSP70 Heat-Shock Proteins ; blood ; Humans ; Lead ; toxicity ; Male ; Occupational Exposure

Leech has a good anticoagulant activity and is one of the raw materials for treatment of many cardiovascular and cerebrovascular diseases. This study was based on in vitro anticoagulant experiments( APTT and PT) to investigate the effects of lead contamination on the anticoagulant effect of leech. At present,the Hirudo circulating in the market are dominated by Whitmania pigra,therefore Wh. pigra were cultivated under a different lead pollution for 50 days. Then,the effects of Wh. pigra extract,extracting from different cultivating environment,on activated partial thrombin time( APTT) and prothrombin time( PT) were determined by automatic coagulation instrument. The results showed that the Wh. pigra extract significantly prolonged the APTT compared with the saline group.The APTT of the lead-high residual Wh. pigra was shorter than that of the blank Wh. pigra. The Wh. pigra extracts from different treatment groups had little effect on PT. The results showed that the lead residue in the Wh. pigra increased with the increase of lead in the cultured soil,the lead residual of the Pb-H group was( 10. 66±2. 79) mg·kg~(-1),which exceeded the lead limit specified in the 2015 edition of the Chinese Pharmacopoeia. The results indicated that growth environment pollution is one of the important factors causing excessive lead in Wh. pigra. Lead pollution will reduce the anticoagulant effect of Wh. pigra and affect its clinical efficacy.
Animals ; Anticoagulants ; Biological Products/pharmacology* ; Blood Coagulation ; Environmental Pollution ; Lead/toxicity* ; Leeches/drug effects* ; Prothrombin Time ; Thrombin Time

OBJECTIVETo observe dynamic changes of blood lead concentration in rats with long-term toxicity test with Goupi Gao by the flame atomic absorption spectrometry, in order to provide reference for safe administration of Goupi Gao.

METHODThe rats were administered with Goupi Gao by high-dose (7 g x kg(-1)), medium-dose (3.5 g x kg(-1)), low-dose (1.75 g x kg(-1)) by external use for consecutively 90 days. Then, the blood samples were collected from the rats before the administration and at 10, 30, 45, 52, 60, 90 d after the administration respectively, as well as 16 d and 28 d after the drug withdrawal. The samples were dispelled with microwave digestion system and then were determined by graphite furnace atomic absorption spectrometry for blood lead levels.

RESULTAccording to methodological study, the standard curve regression equation in this experiment was A = 0.004 9X + 0. 017, r = 0.999 5, with the detection limit up to 0. 380 microg x L(-1). The RSD was 1.4% by precision checks. Blood lead level of mixed blood samples was 175.77 microg x L(-1), whose RSD was 6. 0%. Blood lead concentration gradually increased after low-dose and medium-dose administration to rats and became stable at the 10th day and the 30th day by high-dose. Dose is directly related to blood lead concentration. Meanwhile, the blood lead concentration decreases after the drug withdrawal.

CONCLUSIONThe method of determination in this experiment is so accurate and reliable that it can be used for the determination of blood lead. Long-term and high-dose external use of Goupi Gao can increase blood lead.

Animals ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; toxicity ; Female ; Lead ; blood ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Spectrophotometry, Atomic ; methods ; Time Factors ; Toxicity Tests

Hypertension is one of the most prevalent diseases in the developed and developing countries. Based on the long historical association and the provocative findings of blood pressure effects at low level of lead exposure a study was carried out to determine if an association existed between low blood lead concentration and hypertension. In this study the effects of low-level exposure to lead on blood pressure were examined among 244 adults using atomic absorption spectrometer. For quality assurance purpose certified reference materials i.e., Animal blood A-13, Bovine liver 1577 and cotton cellulose V-9 from IAEA (International Atomic Energy Agency) and NIST (National Institute of Standard Technology) were analyzed under identical experimental conditions. The mean age of hypertensive adults was 52 years (range 43 - 66). The mean values of systolic and diastolic blood pressure were (209+/-11.7) (range 170 - 250) and (117+/-3.9) (range 105 - 140) mmHg respectively. Blood lead concentration ranged from 78 - 201 microg/L with a mean of 139 microg/L and 165 - 497 microg/L with a mean of 255 microg/L in normal and hypertensive adults respectively. Increase in systolic blood pressure was significantly predictive with increase in blood lead levels. Body mass index (BMI) and lipid profile including total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglyceride correlated with blood pressure.
Adult ; Blood Pressure ; drug effects ; Body Mass Index ; Cholesterol ; blood ; Environmental Exposure ; Female ; Humans ; Hypertension ; chemically induced ; Lead ; blood ; toxicity ; Male ; Middle Aged ; Occupational Exposure