Analysis of changes in the rat cardiovascular system under the action of lead intoxication and muscular exercise

Introduction. One of the risk factors for cardiovascular diseases is the toxic metal pollution of the industrial area and the environment. Lead is the most critical of toxic metals. In industrial conditions, the body’s exposure to harmful substances is often combined with muscular work of varying severity. It has not been studied enough how these combinations influence the development of pathological processes associated with harmful exposure. Materials and methods. The subchronic experiment was carried out on white outbred male rats for six weeks. Intoxication was simulated by repeated intraperitoneal injections of lead acetate three times a week. Running was chosen to model the muscle exercise at a 25 m/min speed for 10 minutes 5 days a week. We performed biochemical and electrocardiographic studies. Blood pressure parameters were recorded. Muscle contractility was studied on isolated multicellular preparations of the right ventricular myocardium in isometric and physiological contraction modes. The ratio of myosin heavy chains was determined by the polyacrylamide gel electrophoresis. The sliding velocity of reconstituted thin filaments on myosin using an in vitro motility assay. Results. Physical exercise under lead intoxication normalized the level of calcium and the angiotensin-converting enzyme activity in the blood serum, the voltage of the isoelectric line and the amplitude of the T wave on the electrocardiogram. The combined action of lead and physical exercise showed an increase in the creatinine kinase-MB level. We found that the effect of exercise under lead intoxication on myocardial contractility was ambiguous. The maximum isotonic shortening velocity in trabeculae was normalized, but the maximum rate of strength development in the isometric mode in the papillary muscles decreased to a greater extent than under lead intoxication. The maximum sliding velocity of reconstituted thin filaments and myosin and the heavy chain ratio was partly normalized. Conclusion. In general, muscle exercise attenuated the lead cardiotoxic effects.

Lead Airgun Projectiles Inside the Maxillary Sinuses—Therapeutic Approaches through the Years: A Systematic Review of Case Reports

Background: Shots from commonly available non-gunpowder weapons are a significant cause of facial injuries, especially in pediatric patients. A consequence of such trauma may be the placement of a projectile within the maxillary sinus, which is a therapeutic need with no guidelines for foreign body removal. The purpose of this paper is to discuss the etiology, epidemiology, diagnosis, treatment and prognosis of such cases. Materials and methods: Any cases describing the presence of airgun pellets within the maxillary sinus were included. Animal patients and non-English cases were excluded. The final search using the PubMed, BASE and Google Scholar engines was made on 13 November 2021. The JBI Critical Appraisal Checklist for Case Reports was used to assess the risk of bias. The collected data are presented in tabular form and were subjected to a comparative assessment. Results: In total, reports of seven cases of lead airgun projectiles in the maxillary sinuses were identified, qualified and analyzed. There were no cases of lead intoxication. The bullets were removed by open surgery in the form of antrostomy of the maxillary sinus or with the use of an endoscope. In none of the described cases were complications observed during surgery or postoperative observation. Discussion: This systematic review was based on case reports that differed significantly in quality. The location of the lead foreign body within the maxillary sinuses may be considered favorable over other craniofacial gunshots. The risk of lead intoxication does exist, but such a location of the bullets does not favor it. The removal of projectiles from the maxillary sinuses appears to be easily achievable and does not predispose one to complications.

Is release of rehabilitated wildlife with embedded lead ammunition advisable? Plumbism in a Jaguar Panthera Onca (Mammalia: Carnivora: Felidae), survivor of gunshot wounds

Lead poisoning is a threat to wildlife, particularly after ingestion of lead ammunition derived from hunting activities. Little information, however, is available concerning plumbism in wild animals that survive the trauma associated with gunshot wounds. This study presents a possible example of lead intoxication by embedded pellets in a Jaguar Panthera onca nineteen months after being injured by a shotgun blast. In addition, the possible path of incorporation of lead into the trophic chain after the eventual release and death of an impacted animal, thereby expanding and prolonging the toxic effects of lead ammunition, is discussed. Direct intoxication by ammunition retained in the body of wild animals, as well as the indirect impacts on predators and scavengers that consume their flesh, should be sufficient reasons to reconsider the release of individuals with embedded lead ammunition into the wild.

Lead Levels in Tissues of Local Scavenger Chickens in Maiduguri, Nigeria

Mineral mining activities with environmental pollution in Nigeria resulted in lead intoxication in humans and livestock. The likelihood of lead contamination of the environment from non-mining sources may exist in Maiduguri, Borno state, Nigeria. The study was carried out to evaluate the bioaccumulation of lead in extensively reared local scavenger chickens-LSC (Gallus gallusdomesticus) in Maiduguri. Two hundred samples each of the liver, kidney, intestine, muscle and blood were tested for lead using standard methods in toxicologic evaluation. There were significant (p<0.05) variations in lead levels in the kidney, liver, muscle, intestine and blood of local scavenger chickens. The highest mean lead level (17.0±12.0µg/kg) was observed in the liver, and the lowest leadlevel (4.0±7.0µg/kg) was in the blood. No significant (p>0.05) sex differences existed in the frequency of lead detection. Mean lead level in the liver of males was significantly (p<0.05) higher than that of females with the highest and lowest mean lead levels occurring in the liver and kidney of male chickens, respectively. The highest lead level detected was 414 µg/kg; in the kidney of a female LSC. It was therefore concluded that environmental pollution with lead may be detected in LSCthat bioaccumulate lead; with the liver having the highest affinity.

Long-term lead intoxication of Griffon Vulture (Gyps fulvus Hablizl, 1783) supposedly the result of illegal shooting

The European Griffon Vulture Gyps fulvus is a large-sized scavenger exploiting carcasses of livestock and wild ungulates and thus having a paramount importance in the natural ecosystems. In this study, we report on an adult Griffon Vulture detected with lead levels in the bones over the threshold. After two years of tracking, the bird died. The corpse’s clinical examination and radiography detected the presence of two embedded lead pellets from a healed gunshot wound in its right wing. Quantitative laboratory analysis of lead in bone and liver samples evidencing subclinical/chronic lead intoxication of the Griffon Vulture could potentially be a result of the long-term exposure to the lead originating from the pellets in its wing.