Liver and kidney function tests amongst paint factory workers in Nkpor, Nigeria.

Lead, cadmium, nickel and other industrial metals used as part of paint varnishes have been reported to have adverse health implications. An evaluation study on some toxicological effects of occupational exposure to paint, among 25 occupationally exposed artisans and 25 students (control) of Ichi Technical College, Ichi Ekwusigo Local Government Area, Anambra State, Nigeria was carried out. Heavy metals were analysed by atomic absorption spectrophotometry and standard assay procedures were employed for biochemical parameters. The biochemical indices used include serum electrolytes urea, creatinine, alanine (ALT) and aspartate aminotransferases (AST), alkaline phosphatase (ALP), conjugated and total bilirubin. Others include blood lead, serum cadmium and nickel. Our results showed that occupational exposure of humans to paints increased the blood lead (39 +/- 4 microg/dL), serum cadmium (13 +/- 1 microg/dL) and nickel (63 +/- 1 microg/dL), when compared with non-paint factory workers (PFW) lead (17 +/- 4 microg/dL), serum cadmium (9 +/- microg/dL) and nickel (25 +/- 44 microg/dL), significantly at P < 0.05 lower values were observed for serum sodium (138.96 +/- 0.58 mmol/L), bicarbonate (26.88 +/- 0.39 mmol/L), urea (3.15 +/- 0.13 mmol/L) and creatinine (80.48 +/- 1.04 micromol/L) for paints factory workers when compared with non-paint factory workers, sodium (139.84 +/- 0.62 mmol/L), bicarbonate (26.20 +/- 0.22 mmol/L), urea (3.44 +/- 0.11 mmol/L) and creatinine (80.40 +/- 1.55 micromol/L); at P > 0.05. The activities of AST (10.36 +/- 0.58 micro/L), ALT(8.76 +/- 0.47 micro/L) and ALP (47.12 +/- 3.33 micro/L) in PFW were slightly elevated compared with non-PFW. Our result indicates that occupational exposure of humans to heavy metals in paints may have long term deleterious effects on liver and renal functions. In conclusion, it should be noted that occupational exposure to cadmium or lead among PFW, may compromise the liver and renal functions in man.

Investigation into the nephrotoxicity of Nigerian bonny light crude oil in albino rats.

The effect of bonny-light crude oil was assessed in adult albino rats. The rats were administered with 200, 400, and 800 mg/kg body weight of the crude oil orally for 7 days. Fluid intake was measured daily, initial and final animal body was recorded. The toxic effects on the kidneys were assessed and histological studies carried out. The results revealed that the kidney cells were damaged; crude oil caused a destruction of the renal reserve capacity. There was a significant increase (p ? 0.05) in creatinine in the high dose group (800mg/kg), and a significant decrease (p ? 0.05) in urea concentration. Histological examination indicates that crude oil induced severe pathologic changes in the forms of necrosis and oedema.

Influence of prokinetics on the gastrointestinal transit and residence times of activated charcoal.

OBJECTIVE: To find the effects of prokinetics, saline cathartics and different charcoal doses on the gastrointestinal transit and residence times of activated charcoal (AC). SETTING: Five undergraduate volunteers of College of Health Sciences, Nnamdi Azikiwe University, Nnewi Campus, Anambra State, Nigeria, were studied. METHODS: After an overnight fast, the volunteers were given 10 g and 20 g AC with and without saline cathartics, in a simple cross-over design in which the subjects served as their own control. In another experiment, the volunteers received 10 g AC and magnesium sulphate, with propantheline (as bromide 15 mg), metoclopramide (as hydrochloride 10 mg), placebo liquid or identical placebo capsule. Gastrointestinal transit and residence times of AC were recorded. RESULTS: Increase in the dose of AC significantly (P < 0.05) decreased the transit, but not the residence time of AC. Addition of saline cathartics (Na2SO4 and MgSO4) decreased both the transit and residence times of AC significantly (P < 0.05). Also, administration of propantheline, but not metoclopramide, produced a significant (P < 0.05) decrease in both the transit and residence times of AC. The transit and residence times were statistically (P < 0.05) different in both the magnesium sulphate group, as well as in the placebo liquid and placebo capsule groups. CONCLUSION: Cathartic efficiency is enhanced by alteration of gastrointestinal motility with propantheline.

Saline cathartics and adsorptive capacity of activated charcoal for doxycycline.

The effects of sodium chloride and sodium citrate on the in vitro adsorption of doxycycline to activated charcoal have been studied. Solutions of doxycycline alone and doxycycline with 7.5 mg/ml cathartic solutions were vortex-mixed for 30 s with different quantities of activated charcoal, incubated for 30 min at 37 degrees C and analyzed for free doxycycline spectrophotometrically at 348 nm. Addition of NaCl had a significant (p<0.05) increase while sodium citrate produced a significant (p<0.05) decrease in the adsorption of doxycycline on activated charcoal. In all, the adsorption doxycycline on activated charcoal obeyed quantity-dependent kinetics.

Some plasma pharmacokinetic parameters of isoniazid in the presence of a fluoroquinolone antibacterial agent.

The effects of ciprofloxacin (CP), a fluoroquinolone antibacterial agent, on the extent of absorption of isoniazid (INH) and on some of its pharmacokinetic parameters were investigated in six healthy female volunteers between the ages of 23 and 32 years. The presence of CP led to increase in the amount of INH and to a slight reduction in its peak plasma concentration (Cmax). There was a 1-hour increase in the time to attain Cmax (tmax) of INH, indicating absorption interaction between the two drugs. This absorption interaction was related to inhibition of cholinergic neurotransmission caused by CP, which is capable of inhibiting gastric motility, leading to a delay in gastric emptying. The rate of elimination (K) and plasma half-life (t1/2) of INH were not significantly affected (P = 0.05). The extent of absorption interaction that may have occurred (based on values of 24-hour values for area under the concentration curve, Cmax, Tmax, K, and t1/2) was considered to be of no therapeutic consequence, and the coadministration of the two drugs may be recommended in clinical practice.

Adsorptive capacity of activated charcoal for rifampicin with and without sodium chloride and sodium citrate.

The effects of two saline cathartics (sodium chloride and sodium citrate) on the adsorptive capacity of activated charcoal (AC) for rifampicin were studied. Solutions of rifampicin alone and rifampicin with 7.5 mg/ml cathartic solution were vortex-mixed for 30 s with different quantities of AC. These were incubated for 30 min at 37 degrees C and analyzed for free rifampicin spectrophotometrically at 320 nm. The addition of sodium citrate significantly increased (p<0.05) the adsorptive capacity of AC for rifampicin with a resulting decrease in B-50 values at both the therapeutic and simulated toxic doses. Sodium chloride addition reduced the binding of rifampicin to AC at the toxic doses. The adsorption of rifampicin to activated charcoal, both alone and with the two saline cathartics, obeyed quantity-dependent kinetics. AC may be co-administered with sodium citrate in the management of rifampicin overdose.

Rifampicin pharmacokinetics with and without ciprofloxacin.

We investigated the effect of ciprofloxacin on rifampicin pharmacokinetics in five healthy subjects. Each subject received 600 mg rifampicin with 350 mL of water, and in the second phase, each subject received 600 mg rifampicin plus 500 mg ciprofloxacin with 350 mL of water. In each of the two phases, plasma rifampicin levels were measured from 1 to 24 hours. Treatment with ciprofloxacin significantly increased the half-life and also significantly decreased the maximum peak concentration of rifampicin. Area under the curve time for peak plasma concentration and volume of distribution were not significantly affected. In this study, we found that ciprofloxacin increases the half-life and reduces the maximum concentration of rifampicin in humans.

Effect of activated charcoal on diethylcarbamazine absorption in humans.

We investigated the effect of the oral binder-activated charcoal on the excretion of diethylcarbamazine. Six healthy volunteers were given 150 mg diethylcarbamazine with 350 mL water each. One and 2 weeks later, they received 150 mg diethylcarbamazine plus 7.5 and 15 g activated charcoal, respectively, in 350 mL water as a charcoal slurry. Urinary levels of diethylcarbamazine were measured spectrophotometrically from 1 to 72 hours after ingestion in three different periods. Treatment with activated charcoal led to 5.4% urinary recovery of diethylcarbamazine, decreased excretion rate, and a much lower plateau indicator of reduced absorption. Activated charcoal reduces the absorption and urinary excretion rate of diethylcarbamazine by adsorbing it in the gastrointestinal tract.

Low-dose mercury induces testicular damage protected by zinc in mice.

OBJECTIVES: This investigation was set out to determine whether mercury at a very low dose (4ppm) induces testicular damage on murine testis, and if so whether the toxic effects of mercury could be prevented by zinc. STUDY DESIGN: One of the following solutions was administered in the drinking water of CD-1 male mice: (1) 4ppm HgCl(2); (2) 800ppm ZnCl(2); (3) 4ppm HgCl(2)+800ppm ZnCl(2); or (4) deionised water; for 12 weeks. At the expiration of the treatment period, animals were sacrificed, testes excised and weighed, and epididymal sperm number taken. The testes were processed for histological examination. RESULTS: Both zinc and mercury significantly (p<0.05) decreased the absolute and relative testicular weights, with mercury producing the highest reduction in weight. Mercury reduced significantly (p<0.05) the epididymal sperm number, while zinc and mercury/zinc produced statistically same effect with control on the sperm number. Histological study showed that mercury at the concentration employed produced remarkable degenerative lesions on the testes, as the zinc-treated group showed a normal morphology. Majority of the animals in the mercury/zinc-treated group exhibited complete or partial protection as evidenced by the morphology of the seminiferous tubules. CONCLUSION: Zinc prevents mercury-induced testicular damage in mouse. These findings highlight the risks exposure to inorganic mercury might pose to male reproduction of mice, and suggests possible therapy with zinc. Study in humans is therefore advocated.

Acceleration of body clearance of diethylCarbamazine by oral activated charcoal.

The effect of activated charcoal (AC) on body clearance of diethylcarbamazine (DEC) was investigated in six healthy volunteers. On three occasions at weekly intervals, each subject received 150 mg of DEC with 350 ml of water. One and two weeks later, 150 mg of DEC plus 7.5 g and 15 g of AC, respectively, in 350 ml of water as a charcoal slurry. The non-renal clearance of DEC expressed as the total body clearance of DEC was increased after treatment with AC. The 45.2, 79.6 percent and 58.6, 81.6 percent reductions in maximum concentration and area under the concentration-time curve, respectively, suggest an appreciable adsorption of DEC by AC (7.5 and 15 g) in the gut. Serum eliminating half-life was decreased upon treatment with AC (7.5 and 15 g). These results indicate that AC accelerates the body clearance of DEC by increasing non-renal elimination of the drug.

Pharmacokinetics of diethylcarbamazine: prediction by concentration in saliva.

The concentration of diethylcarbamazine in saliva was used to determine pharmacokinetic parameters, in comparison to plasma and urine concentrations. Six healthy adult male volunteers were administered 150 mg diethylcarbamazine with 400 ml of water. At seven different time intervals, blood, urine and saliva samples were taken, and different pharmacokinetic parameters measured. The plasma-saliva concentration ratio was calculated as 1.53 whereas the observed ratio was 3.82. The half lives, times to reach peak plasma concentration, and elimination rate constants did not show any significant difference in the different samples. The plasma peak concentration and areas under the curve were significantly (p<0.05) increased from those of the saliva. At 24 h, when diethylcarbamazine was absent in urine, the plasma and saliva concentrations were almost zero. Diethylcarbamazine is secreted in saliva, and its concentration in saliva can be used to monitor drug therapy.

Zinc protection of mercury-induced hepatic toxicity in mice.

The actions and interactions of heavy metals on certain organ functions have been of concern, since occupational exposure to certain metals results in impairment of functions. Studies were carried out to determine the effects of zinc (Zn) and mercury (Hg) on murine liver. CD-1 male mice were administered 4 ppm HgCl2, 800 ppm ZnCl2, 4 ppm HgCl2+800 ppm ZnCl2 or deionized water in their drinking water for 12 weeks. Histological evaluation of the liver confirmed the toxic effects of Hg, as well as the normal morphology of the Zn-exposed animals. A combined treatment of both metals resulted in protection of the Hg-induced liver damage by Zn. The results of this experiment indicate that Hg has a toxic effect on liver, while Zn has a protective action against such toxic effects.

Some pharmacological properties of Synclisia scabrida II.

The effect of the aqueous extract of S. scabrida on behaviour, and as an analgesic and antiulcer agent were studied. The extracts did not produce significant central nervous system action, or analgesia but had significant antiulcer activity against aspirin induced ulcer. The extract showed anticholinergic and antihistaminergic properties.