Progressive delayed respiratory complications of sulfur mustard poisoning in 43 Iranian veterans, three decades after exposure.

The most common delayed complication of sulfur mustard (SM) poisoning has been observed in the respiratory tracts. It was thus aimed to investigate the delayed respiratory complications in SM-exposed patients around 25 years before the study. Forty-three veterans with more than 25% disability of due to SM poisoning were investigated. Clinical examinations as well as pulmonary function test (PFT) were performed. High-resolution computed tomography (HRCT) of the lungs was done as clinically indicated. Triad of chronic cough, dyspnea, and expectoration were the most common symptoms that were recorded in 88.2%, 88.2%, and 64.7% of the patients, respectively. PFT abnormalities were detected in 44.18% of the patients. Restrictive pattern was the most common (41.86%), while pure obstructive pattern did not detect at all. Mixed pattern was significantly correlated with higher disability percentages among the veterans ( p < 0.001). Significant reverse correlation between the disability percentages and forced expiratory volume in 1 s/forced vital capacity ratio was obtained ( p = 0.010, r = -0.389). Air trapping was the most common abnormality in HRCTs (50%). Bronchiectasis (25%), pulmonary fibrosis (25%), and ground-glass attenuation (16.66%) were other common HRCT findings. Comparing with the previous studies on these patients, more restrictive and mixed pattern were observed. Moreover, bronchiolitis, bronchiectasis, and lung fibrosis were the main pathological findings in these patients.

Occupational Metallic Mercury Poisoning in Gilders.

Occupational exposure to elemental mercury vapor usually occurs through inhalation during its utilizations. This leads to a variety of adverse health effects. In some Islamic cities, this type of poisoning may occur during gilding of shrines using elemental mercury with gold. Herein, we report on three male patients aged 20-53 years, who were diagnosed with occupational metallic mercury poisoning due to gilding of a shrine. All patients presented with neuro-psychiatric disorders such as anxiety, loss of memory and concentration, and sleep disorders with high urinary mercury concentrations of 326-760 µg/L upon referring, 3-10 days after cessation of elemental mercury exposure. Following chelating therapy, the patients recovered clinically and their mercury concentrations declined to non-toxic level (<25 µg/L). Health, environmental and labor authorities, as well as the gilders should be aware of the toxicity risk of exposure to metalic mercury during gilding in closed environments and act accordingly.

Concentrations of mercury, lead, chromium, cadmium, arsenic and aluminum in irrigation water wells and wastewaters used for agriculture in Mashhad, northeastern Iran.

BACKGROUND: Contamination of water by toxic chemicals has become commonly recognized as an environmental concern. Based on our clinical observation in Mashhad, northeastern Iran, many people might be at risk of exposure to high concentrations of toxic heavy metals in water. Because wastewater effluents as well as water wells have been commonly used for irrigation over the past decades, there has been some concern on the toxic metal exposure of crops and vegetables irrigated with the contaminated water. OBJECTIVE: To measure the concentrations of mercury, lead, chromium, cadmium, arsenic and aluminium in irrigation water wells and wastewaters used for agriculture in Mashhad, northeastern Iran. METHODS: 36 samples were taken from irrigation water wells and a wastewater refinery in North of Mashhad at four times--May 2008, March 2009, and June and July 2010. Atomic absorption spectrometry was used to measure the concentration of toxic metals. Graphite furnace was used for the measurement of lead, chromium, cadmium and aluminum. Mercury and arsenic concentrations were measured by mercury/hydride system. RESULTS: Chromium, cadmium, lead and arsenic concentrations in the samples were within the standard range. The mean±SD concentration of mercury in irrigation wells (1.02±0.40 µg/L) exceeded the FAO maximum permissible levels. The aluminum concentration in irrigation water varied significantly from month to month (p=0.03). All wastewater samples contained high mercury concentrations (6.64±2.53 µg/L). CONCLUSION: For high mercury and aluminum concentrations, the water sources studied should not be used for agricultural use. Regular monitoring of the level of heavy metals in water and employing the necessary environmental interventions in this area are strongly recommended.

Health aspects of organophosphorous pesticides in asian countries.

Organophosphorous (OP) pesticides are used frequently in agriculture, particularly in Asian countries over the past decades. Poisoning by these agents, either as acute or chronic in these nations, is a serious health problem. OP pesticides residue in fruits and vegetables that may not induce early clinical features, could also affect the human health. Therefore, medical and health professionals should be aware and learn more on the toxicology, prevention and proper management of OP poisoning. The well-known mechanism of OP toxicity is the inhibition of acetyl cholinesterase, resulting in an accumulation of acetylcholine and continued stimulation of acetylcholine receptors. Therefore, they are also called anticholinesterase agents. Determination of blood acetyl cholinesterase and butyryl cholinesterase activities remains a mainstay for the rapid initial screening of OP pesticides. Quantitative analysis of OP and their degradation products in plasma and urine by mass spectrometric methods is a more specific method, but is expensive and limited to specialized laboratories. Therefore, history of OP pesticides exposure and clinical manifestations of a cholinergic syndrome is sufficient for management of the exposed patients. However, electrophysiological tests may be required for the diagnosis of delayed neuropathy of OP poisoning. The standard management of OP poisoning includes decontamination, atropine sulphate with an oxime. Recent advances focus on blood alkalinisation and magnesium sulphate as promising adjunctive therapies. Preventive measures in OP exposure are of great importance in human health in developing countries. Therefore, regulations and controls on safe use of OP particularly in Asian countries are recommended.

Occupational lead poisoning in workers of traditional tile factories in Mashhad, Northeast of Iran.

BACKGROUND: Occupational lead poisoning is a health problem in Iran. It has not previously been studied in traditional tile makers. OBJECTIVE: To determine the prevalence of lead poisoning and its complications in traditional tile workers in Mashhad, Northwest of Iran. METHODS: We visited workers in two traditional tile factories and collected data by direct history taking and physical examination. Blood and urine lead concentrations were measured by heated graphite atomization technique. RESULTS: Overall, 108 men with mean±SD age of 37±7.8 years were studied. The mean±SD length of daily lead exposure was 9.8±6 years. The mean±SD blood lead concentration was 520.5±323.2 µg/L. The main objective clinical findings were the presence of lead line (64.8%), peripheral neuropathy of the upper extremities (37%), depressed deep tendon reflexes in the upper extremities (25.7%), tremor (23.3%), peripheral neuropathy of the lower extremities (17%) and abdominal tenderness (15.1%). The subjective findings were mainly attributed to the central nervous system and included loss of memory (57%), moodiness (56.1%), agitation (47.7%), drowsiness (36.4%) and headache (29.9%). There was no statistically significant correlation between the blood lead concentration and glomerular filtration rate. However, there were significant correlations between the blood lead concentration and each of the urine lead concentration (p<0.001), diastolic blood pressure (p = 0.04), serum triglyceride level (p = 0.043), high density lipoprotein level (p = 0.012), and basophilic stippling (p = 0.048). Blood lead level, however, did not have any significant correlation with the presence of lead line. CONCLUSION: In traditional tile workers, lead toxicity is not uncommon and the toxic effects of lead were found more often on the teeth (bone), central and peripheral nervous system, hematological and lipid profiles than on the renal function.

Spider bite (latrodectism) in Mashhad, Iran.

BACKGROUND: Spider (Latrodectus tredecimguttatus) bites are relatively common in North East Iran. They induce morbidity and rarely mortality. We aimed to investigate clinical, electrocardiographic and para-clinical changes in patients with this bite. METHODS: All consecutive patients admitted with suspected spider bites between September 2005 and September 2006 were studied prospectively. RESULTS: Spider bites accounted for 56 cases (0.5% of all poisoning, 21% of all admitted envenomated). The patients' mean (SD) age was 32 (16) years. The most common findings were pain (90%) mainly in their back (45%), stomach (35%), lower limbs (33%), upper limbs (19%) and chest (14%). Other clinical findings included were sweating (55%), chills (29%), dyspnea (25%), flushing (14%), spasm (12%), headache (12%), nausea (12%) and vertigo (12%). On electrocardiograph (ECG); ST segments were depressed in 25% of cases in at least two of the pre-cordial leads. Laboratory findings were in normal ranges. All the patients recovered following supportive and symptomatic treatment (no anti-toxin available in Iran), with a mean hospitalization period of 1.9 (1.3) days. CONCLUSIONS: Spider (L. Tredecimguttatus) bite is relatively common in Mashhad, which induces latrodectism with relatively different findings and cardiac toxicity. ECG monitoring should be considered, particularly when specific anti-toxin is not available.

Delayed head and neck complications of sulphur mustard poisoning in Iranian veterans.

OBJECTIVE: Sulphur mustard is a chemical warfare agent which was used against Iranian combatants and civilians between 1983 and 1988. The purpose of this study was to document the delayed toxic effects of sulphur mustard in Iranian veterans, focussing on head and neck complications. PATIENTS AND METHODS: This was a two-year, prospective, descriptive study of 43 male Iranian veterans aged 34 to 48 years (mean 41.8 years) who were moderately disabled or worse due to sulphur mustard poisoning. Investigations were performed with consent, including haematological, biochemical and immunological tests, spirometry, chest X-ray, high resolution computed tomography of the lungs, and skin biopsies. Further investigations and interventions were performed as clinically indicated. RESULTS: The most affected sites were the lungs (95 per cent), peripheral nerves (77 per cent), skin (73 per cent), eyes (68 per cent), and head and neck (16.2 per cent). Of seven patients with mostly head and neck complications, four had a skin disorder (hyperpigmentation in all four, an erythematous, papular rash in two, and dry skin in one). Two patients had thyroid cancer (undifferentiated thyroid carcinoma in one and papillary carcinoma of a thyroglossal cyst in the other, 12 and 14 years after sulphur mustard exposure, respectively). One patient had nasopharyngeal carcinoma, 12 years after sulphur mustard exposure. CONCLUSION: Carcinomas of the thyroid and nasopharynx in three patients with sulphur mustard exposure are reported for the first time.

Evaluation of allicin for the treatment of experimentally induced subacute lead poisoning in sheep.

Garlic (Allium sativum) is known to reduce lead toxicity in some species of animals. The objective of this study was to evaluate the efficacy of allicin, one of the most active components of garlic, in the treatment of subacute lead intoxication in sheep. Nine female sheep weighing 25-29 kg orally received a daily dose of 80 mg/kg body weight of lead acetate for 5 days. The animals were then assigned into two groups. Group 1 did not receive any further treatment and was used as the control group and group 2 was treated orally by 2.7 mg/kg body weight of allicin twice daily for 7 days. Within one day following allicin treatment, group 2 blood lead levels were significantly lower than that in group 1 (mean of 616.9 microg/l and 290.02 microg/l, respectively; P < 0.05). Also, allicin treatment significantly reduced kidney lead content and considerably reduced bone and ovary lead contents. These results suggest that allicin might have some therapeutic effects on lead poisoning.

Chronic health effects of sulphur mustard exposure with special reference to Iranian veterans.

The widespread use of sulphur mustard (SM) as an incapacitating chemical warfare agent in the past century has proved its long-lasting toxic effects. It may also be used as a chemical terrorist agent. Therefore, all health professionals should have sufficient knowledge and be prepared for any such chemical attack. SM exerts direct toxic effects on the eyes, skin, and respiratory tissue, with subsequent systemic action on the nervous, immunological, haematological, digestive, and reproductive systems. SM is an alkylating agent that affects DNA synthesis, and, thus, delayed complications have been seen since the First World War. Cases of malignancies in the target organs, particularly in haematopoietic, respiratory, and digestive systems, have been reported. Important delayed respiratory complications include chronic bronchitis, bronchiectasis, frequent bronchopneumonia, and pulmonary fibrosis, all of which tend to deteriorate with time. Severe dry skin, delayed keratitis, and reduction of natural killer cells with subsequent increased risk of infections and malignancies are also among the most distressing long-term consequences of SM intoxication. However, despite a lot of research over the past decades on Iranian veterans, there are still major gaps in the SM literature. Immunological and neurological dysfunction, as well as the relationship between SM exposure and mutagenicity, carcinogenicity, and teratogenicity are important fields that require further studies, particularly on Iranian veterans with chronic health effects of SM poisoning. There is also a paucity of information on the medical management of acute and delayed toxic effects of SM poisoning-a subject that greatly challenges health care specialists.

Pattern of acute poisonings in Mashhad, Iran 1993-2000.

Drugs and chemicals are almost easily available in Iran. Natural toxins as poisonous plants and animals also exist in most parts of the country. Therefore, acute poisonings, either intentional or accidental and also drug abuse/addiction are common in Iran. In spite of these difficulties there is no center for poison control and surveillance in this country to gather information and analyse data. The files of a systematic randomised ten percent of all hospital-referred poisoned patients from 21 March 1993 to 20 March 2000 in Imam Reza (p) University Hospital of Mashhad (71589 cases) were screened retrospectively. Young adults (40.3%) and school children (22.9%) were the most vulnerable group. Mean age was 22.3 (S.D. 14.38) years with a minimum of less than one and a maximum of 98 years old. A female predominance was found (53.4%). Intentional poisoning was more common (54.4%) than accidental exposures (45.2%). Fourteen cases were classified as criminal poisoning. 79.7% of exposures were via ingestion, followed by dermal exposures (14.1%), and inhalation (6.2%). The majority (83.7%) of patients were from urban areas. Most patients (68.6%) were treated in the Emergency Toxicology Clinic and discharged, 19.2% were temporarily hospitalized and 11.3% were hospitalized for 24 hr. Main groups of poisons were pharmaceuticals (61.4%), chemicals (22.8%), and natural toxins (16.6%). The overall number of poisoned patients was higher in spring and summer (62.8%). In conclusion, acute poisonings, particularly self-poisonings, are common in Iran. Since medical documentation is not routinely provided in this country the results of this retrospective study can be used for surveillance. Establishment of fluent data gathering and analysis within the local health system are challenges for the future.

Urinary mercury excretion following amalgam filling in children.

OBJECTIVES: Dental amalgam is the major source of inorganic mercury exposure in the general population. Dental amalgam contains approximately 50% mercury, which is a toxic element. Since children are more at risk for mercury toxicity, we aimed to study prospectively the effects of amalgam filling on urinary mercury excretion in 5- to 7-year-old children. METHODS: Children admitted to the Pedodontics Department with no previous amalgam filling, and in a good state of health with one or more carious posterior teeth, were selected. All fillings were placed in one session for each child using Sina (Iran) amalgam powder and Degussa (Germany) mercury, which were mixed by an automated electric amalgamator (Dentomate 3, Germany). Urinary mercury concentrations were estimated before and 9-12 days after amalgam filling by atomic absorption using the mercuric hydride system. RESULTS: Forty-three children (20 male, 23 female) aged 5.95+/-0.92 years and weighing 19.09+/-3.10 kg were studied. Urinary mercury concentrations before and after amalgam filling were 3.83+/-2.45 and 5.14+/-3.14 microg/L, respectively (p = 0.001). There were no statistically significant correlations between the urinary mercury concentrations and any other variables, including the number and surfaces of filled teeth, weight, age, and sex. CONCLUSION: Although there were highly significant increases in urinary mercury concentrations after amalgam filling, no significant correlation was found between the urinary mercury concentration and the amounts of filled amalgam. Additional investigation is required concerning the effects of mercury release from amalgam.

Treatment of organophosphate poisoning. Experience of nerve agents and acute pesticide poisoning on the effects of oximes.

Organophosphate (OP) compounds have been used as pesticides and in chemical warfare (nerve agents). Two nerve agents, tabun and sarine, were used by the Iraqi army against Iranian troops and innocent people. Hundreds of the exposed combatants died in the field. Atropine sulphate has been used successfully in large doses to counteract the muscarinic effects of OP poisoning. The effects of oximes in human OP poisoning have not been well studied. Our aim was to study the effects of obidoxime and pralidoxime in OP pesticide poisoning. The patients were divided into three groups: atropine (A), obidoxime + atropine (OA) and pralidoxime + atropine (PA). Sixty-three patients (33 males, 30 females) with a mean age of 25 years were studied in different groups (43 A, 22 OA and 8 PA). There were no statistical significant differences in major clinical findings and acetylcholinesterase (AChE) activity on admission between the groups. Significant changes were observed during the treatment. Notwithstanding the severity of intoxication--particularly respiratory complications were more observed in the OA and PA groups--there were no fatalities in the PA group, whereas 4 (9%) and 6 (50%) patients in the A and OA groups died, respectively. AChE reactivation was only observed in the PA group, although it was not statistically significant (r = 0.4747). There was a good relationship between the AChE reactivation and outcome of the patients. High doses of obidoxime (8 mg/kg followed by 2 mg/kg/h) were found to be hepatotoxic and should be avoided. High doses of pralidoxime (30 mg/kg followed by 8 mg/kg/h) did not induce serious side effects and may be effective in some OP pesticides poisoning.

Ethnic differences in the renal sodium dopamine relationship. A possible explanation for regional variations in the prevalence of hypertension?

Over the last three years we have carried out studies on the urine output of both sodium and dopamine in five different ethnic groups: whites, Ghanaians, Zimbabweans, Iranians and Thais. Sodium was measured by ion specific electrode and dopamine by HPLC with electrochemical detection (using epinine as an internal standard). In several groups salt loading studies were also carried out. The five ethnic groups differed substantially with regard to the correlation between their urinary sodium and dopamine outputs. Three groups (whites, Thais and Zimbabweans) showed a strong positive correlation (P less than .001) and this may reflect their traditionally salt rich diet. In two groups (Ghanaians and Iranians) there was no correlation and this may reflect a salt scarce environment. Taken together with our previously reported studies showing that normotensive Ghanaians do not mobilize dopamine on salt loading, this would suggest that certain ethnic groups are predisposed to develop hypertension on salt loading--that is, they are 'salt sensitive.' This genetic trait may have passed from the West Coast of Africa, with the slaves, to America and the Caribbean. Other workers have reported deficiencies in vasodilator systems in the American black, such as dopamine, kallikrein and the renal prostaglandins. These defects may lead to the nosologic entity of 'low renin' hypertension, well described in American blacks, and could open up avenues of therapy based either on DA1 activators (such as fenoldopam) or on renal prodrugs (such as gludopa).

Ethnic differences in the renal dopamine response to an oral salt load.

Dopamine is a natriuretic hormone which is synthesised within the kidney. We have previously found that some ethnic groups (e.g. British Caucasians and Thais) show strong positive correlations between 24 h urinary sodium and dopamine outputs. However no such relationship was found in Iranians and black West Africans. We have now studied the effect of oral salt loading (200 mmol) on 24 h urinary sodium and dopamine outputs in individuals from these four ethnic groups. The Caucasians showed a significant increase (35%) in urinary dopamine output after salt loading. However, there was no dopamine response to the salt load in the Ghanaians and the Iranians. The Thais were all vegetarians and fell into two distinct groups with either an increase ('positive responders') or decrease ('negative responders') in dopamine output after salt loading. The negative responders all had a very low mean control sodium output (60 +/- 21 mmol/24 h) compared to the positive responder Thais and the other three ethnic groups which all had mean sodium outputs greater than 115 mmol/24 h. We hypothesize that in some racial groups the uncoupling of the renal sodium-dopamine relationship may be an inherited mechanism to help conserve sodium (as in the Ghanaians and the Iranians) or an adaptive change to being restricted to a low salt diet for a long time (as in the Thai 'negative responders').

Ethnic differences in the renal sodium-dopamine relationship: a possible explanation for regional variation in the prevalence of hypertension?

Twenty-four-h urinary sodium and dopamine output by normotensive adults from 5 different ethnic groups have been measured. The groups differed substantially in the correlation between the urinary output to sodium and dopamine. Those with a traditionally salt rich diet (Thais, Caucasians, Zimbabweans) showed a strong positive correlation (p less than 0.001), whereas no such relationship was found in West Africans and Iranians, who come from traditionally salt scarce environments. It is hypothesised that in some races the lack of or uncoupling of the renal sodium-dopamine relationship, possibly as a mechanism to help conserve dietary sodium, predisposes to the development of hypertension when the individuals encounter a salt rich diet.

Further ethnic differences in the renal sodium-dopamine relationship: its uncoupling in Iranian but not in Thai normotensive subjects.

Dopamine is a natriuretic hormone and is synthesized in the kidney in response to a sodium load. This relationship results in a positive correlation between urinary sodium and dopamine outputs. Uncoupling of the renal sodium-dopamine relationship is reflected in a loss of this correlation and will result in the sluggish excretion of a sodium load. We measured 24-h urinary sodium and dopamine outputs in Thais and Iranians, who traditionally have very different dietary salt environments (salt-rich and salt-scarce, respectively). There was a highly significant positive correlation between sodium and dopamine in the Thais (r = 0.53, P less than 0.001) but no suggestion of such a correlation in the Iranians (r = 0.03). We hypothesize that in some races the uncoupling of the renal sodium-dopamine relationship, possibly as a mechanism to help conserve dietary sodium, predisposes the race to the development of hypertension when the individuals encounter a salt-rich diet.

Diuresis or urinary alkalinisation for salicylate poisoning?

Forty-four adults with aspirin poisoning were treated with oral fluids only, standard forced alkaline diuresis, forced diuresis alone, or sodium bicarbonate (alkali) alone. Alkali alone was at least as effective and possibly more effective than forced alkaline diuresis in enhancing salicylate removal. Unlike the diuresis regimens it did not cause fluid retention or biochemical disturbances. The renal excretion of salicylate depends much more on urine pH than flow rate, and forced diuresis alone had little useful effect. In overdosage aspirin causes sodium and fluid retention and may impair renal function. Attempts to force a diuresis are potentially hazardous and the spurious fall in plasma salicylate concentration caused by haemodilution gives a false impression of efficacy. Further studies are required to determine the optimum treatment for salicylate poisoning.