Exposure of Male Farmers and Nonfarmers to Neonicotinoid Pesticides in the South-West and Littoral Regions of Cameroon: A Comparative Study.

Pesticides, especially the newly developed neonicotinoids, are increasingly used in many countries around the world, including Cameroon, to control pests involved in crop destruction or disease transmission. Unfortunately, the pesticides also pose tremendous environmental problems because a predominant amount of their residues enter environmental matrices to affect other nontargeted species including humans. This therefore calls for continuous biomonitoring of these insecticides in human populations. The present study sought to assess the neonicotinoid insecticide exposures in two agrarian regions of Cameroon, the South-West region and Littoral region. The study involved 188 men, including 125 farmers and 63 nonfarmers. Spot urine samples were obtained from these subjects and subjected to liquid chromatographic-tandem mass spectrometric analysis for concentrations of neonicotinoid compounds, including acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, nitenpyram, thiamethoxam, and N-dm-acetamiprid. Neonicotinoid compounds were detected in all study participants, and residues of all the screened pesticides were detected among participants. N-dm-Acetamiprid and imidacloprid were the most prevalent among the subjects (100.0% and 93.1%, respectively), whereas nitenpyram was less common (3.2%). The median values of imidacloprid and total urinary neonicotinoid concentrations were elevated among farmers (0.258 vs. 0.126 µg/L and 0.829 vs. 0.312 µg/L, respectively). Altogether the findings showed that both the farmer and nonfarmer study populations of Cameroon were exposed to multiple residues of neonicotinoids, with relatively higher levels of pesticides generally recorded among farmers. Although exposure levels of the neonicotinoids were generally lower than their respective reference doses, these results warrant further research on the health risk evaluation of multiple residues of the pesticides and reinforcement of control measures to minimize the exposure risks, especially among farmers. Environ Toxicol Chem 2024;43:952-964. © 2024 SETAC.

Antioxidant content and activity of stem and leaf extracts of Gouania longipetala Hemsl. (Rhamnaceae).

Background: Gouania longipetala Hemsl. is a scandent shrub used in traditional medicine for the management of different ailments such as gout, female infertility, heart diseases, diabetes, and malaria. Pathophysiology of the diseases is generally associated with oxidative stress. Antioxidant properties of G. longipetala have not yet been well elucidated. Aims: This study aimed to evaluate the antioxidant content and antioxidant activity of methanol extracts from the plant's stems and leaves. Materials and methods: Methanol extracts from the plant stems and leaves were screened for phytochemical components with antioxidant properties (Vitamin C, total phenolics, and flavonoids). The antioxidant reducing power of the extracts as well as its effects on lipid peroxidation and catalase were also evaluated in vitro using biochemical assays. Results: Leaf extract was richer than stem extract in different antioxidants such as Vitamin C, phenolics, and flavonoids. Both leaf and stem extracts showed similar inhibitory effect on lipid peroxidation and stimulatory effect on catalase activity, while leaf extract had higher ferric antioxidant effect than stem extract. Conclusion: Both extracts from G. Longipetala possessed antioxidant content, though activities with leaf extract displayed higher antioxidant properties than stem extract.

Assessment of visceral adiposity index and lipid accumulation product index as markers of chronic kidney disease among diabetic and hypertensive patients at the Bamenda Regional Hospital, Cameroon: a cross-sectional study.

Introduction: very limited studies have emphasized the importance of visceral adiposity index (VAI) and lipid accumulation product index (LAPI) in the prevention and management of chronic kidney disease (CKD) especially in diabetic and hypertension patients in developing countries including Cameroon. This study aimed at assessing whether VAI and LAPI are markers of CKD among diabetic and hypertensive patients at the Bamenda Regional Hospital, Cameroon. Methods: this analytical cross-sectional study was conducted at Bamenda Regional Hospital and involved 200 diabetic and/or hypertensive patients, including 77 males and 123 females. The participant´s anthropometric indices, biochemical parameters, VAI, LAPI, and glomerular filtration rate were investigated. A structured questionnaire was used to assess some risk factors of CKD and participant lifestyle. Results: the overweight (41%) and obesity (34%) statuses were prevalent in the population. A considerable proportion of subjects had elevated total cholesterol (46%), low-density lipoprotein (LDL) cholesterol (37.50%), triglycerides (24.5%), urea (40.5%) and creatinine (53.5%) levels. Stage 1 to 3 CKD was largely present in the elderly (>54-year-old) affecting the majority of patients (57.5%). Low education level and lack of physical activity were significantly associated with the prevalence of CKD (p < 0.001). On the contrary to creatinine (unadjusted OR = 1.36; 95% CI: 1.13-1.62), urea (unadjusted OR = 1.02; 95% CI: 1.01-1.03), HDL (unadjusted OR = 0.87; 95% CI: 0.78-0.97), total cholesterol/HDL ratio (unadjusted OR = 1.38; 95% CI; 1.12-1.71), VAI (unadjusted OR = 1.13; 95% CI: 1.05-1.22) and LAPI (unadjusted OR = 1.00; 95% CI: 1.00-1.00) were significantly associated with CKD status of the patients while HDL was negatively associated (unadjusted OR = 0.87; 95% CI: 0.78-0.97). The 9.905 and 5679 cut-offs of VAI and LAPI respectively for CKD discrimination obtained high sensitivity (75.0%) and specificity (≥79.6%). Conclusion: visceral adiposity index and LAPI were associated with CKD among diabetic and hypertensive patients. Visceral adiposity index and LAPI could be user-friendly tools for the early diagnosis of CKD among these categories of patients in Cameroon.

Occupational use of agrochemicals results in inhibited cholinesterase activity and altered reproductive hormone levels in male farmers from Buea, Cameroon.

The efficiency of agro pesticides and fertilizers in eliminating pests and scaling up crop yield has motivated farmers to increase their use. Unfortunately, health hazards caused on farmers by these agrochemicals are of growing concern, though not well elucidated. In order to evaluate the effects of occupational exposure to agrochemicals on some key parameters of male farmers' health in Buea Subdivision, Cameroon, a total of 101 men, including 62 farmers using the agrochemicals and a reference population of 39 men not involved in occupational utilization of the agrochemicals, were interviewed on use of protective equipment, exposure symptoms and reproductive health status. Thereafter, serum cholinesterase [acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)] activities, total antioxidant capacity and reproductive hormones [follicle-stimulating hormone (FSH), luteinizing hormone and testosterone] were assessed. Results revealed that farmers mainly used insecticides followed by fungicides, herbicides and fertilizers, but with inadequate protective measures. The use of agrochemicals resulted in several exposure symptoms including weakness, itches, burning sensation, headache, sneezing, coughing and vomiting, as well as decrease in serum AChE activity when compared to the reference population. The agrochemicals impacted negatively on the farmers' reproductive health as evidenced by increased FSH levels. Taken altogether, these results suggested that exposure to agrochemicals adversely affects farmers' health. Therefore, there is a need to further sensitize the farmers on the use of protective equipment to mitigate the exposure and resulting health hazards.

Evaluation of the Effects of Agro Pesticides Use on Liver and Kidney Function in Farmers from Buea, Cameroon.

Agro pesticides are increasingly used worldwide to increase crop production. However, health hazards resulting from human exposure to these chemicals, especially from agricultural areas of developing countries have been a growing concern. The objective of this study was to evaluate the impact of occupational exposure to agro pesticides on the health of farmers in the Buea subdivision, which is one of the major agrarian areas in Cameroon. The study was transversal and involved 90 participants including 58 farmers using pesticides and a reference population of 32 men not involved in occupational use of agro pesticides. The participants were interviewed on agro pesticide use and their health status. Thereafter, blood samples were collected from the participants and used for the assessment of biochemical markers of the liver (alanine aminotransferase and aspartate aminotransferase) and the kidney (creatinine and uric acid) function. Results revealed that farmers frequently used insecticides, fungicides, and herbicides in their farming activities. Farmers reported several acute health symptoms related to pesticides use with the common ones being skin rash, eye irritation, and face burn. When compared to the reference population, the farmers showed significantly elevated (p < 0.01) alanine aminotransferase activity. However, other parameters investigated were not affected significantly. These results suggested that farmers were exposed to 3 different classes of agro pesticides, which induced eye and skin affections. Pesticides exposure resulted in alterations of the liver function hence the increased serum alanine aminotransferase activity. Therefore, there is a need to sensitize the farmers on toxicity and liver alteration potential of agro pesticides and the importance of appropriate protective equipment that may minimize exposure.

Bisphenol A differentially affects male reproductive function biomarkers in a reference population and agro pesticides users from Djutitsa, Cameroon.

The consequences of bisphenol A (BPA) exposure on male reproductive function were studied in two populations from Cameroon, farmers using agro pesticides in Djutitsa (rural area) and townsmen in Yaoundé (urban area, Centre region). Urinary BPA concentration from all participants was measured, and the values were correlated with biochemical markers of male reproductive function. The data showed that BPA could be detected in 92.6% of urine participants, with an average concentration of 2.18 ± 1.97 µg/g creatinine but with no significant difference between the urinary BPA concentration from rural and urban populations. From BPA urinary concentration, the BPA average daily intake was estimated to be 0.06 ± 0.05 µg/kg/day (3.51 µg/day per individual) in the Cameroon population. Interestingly, free and bioavailable testosterone concentrations and estradiol/testosterone ratio correlated with BPA levels in the overall population. When data were analysed according to residence, BPA correlated with total testosterone levels ( r = -0.433) and estradiol/testosterone ratio ( r = 0.338) in the urban residents only, while the rural population exhibited significant increases in sex-hormone-binding globulin with increased BPA exposure. Our data showed that the male Cameroon population is exposed to BPA but that inconstant BPA association to endocrine reproductive markers suggests that other environmental factors in combination with BPA exposure might influence testicular function.

Parastar insecticide induced changes in reproductive parameters and testicular oxidative stress biomarkers in Wistar male rats.

Parastar is an insecticide formulation of lambda-cyhalothrin and imidacloprid, and it is largely used for crop production improvement in Santa, North West Region of Cameroon. This study aimed at evaluating the effects of Parastar on reproductive parameters and testicular oxidative stress in adult albino Wistar male rats. Twenty rats (154 g ± 28 g) were divided into four groups of five animals each and treated daily with either distilled water (10 mL/kg), 1.25, 2.49 or 6.23 mg/kg of Parastar, respectively, for 35 days. After treatment, animal reproductive function was evaluated through fertility tests, sperm characteristics, testosterone levels and organ weights, while oxidative stress biomarkers were determined on testicular homogenates. Parastar administration resulted into increased seminal vesicle and prostate weights, while body weight remained unaffected. Parastar dose-dependently reduced sperm density and mobility, and the highest dose decreased serum testosterone levels. Parastar also modulated stress biomarkers with increased thiobarbituric acid reactive substances levels, decreased glutathione levels and inhibition of catalase and superoxide dismutase activities. In conclusion, Parastar negatively affected male reproductive function through alteration of testosterone levels, sperm parameters and induction of oxidative stress in rats.

QuEChERS-based method for the determination of carbamate residues in aromatic herbs by UHPLC-MS/MS.

A new reliable, fast and highly sensitive method based on ultra-high performance liquid chromatography tandem mass spectrometry has been developed and validated for the determination of 28 carbamates in aromatic herbs. A modified QuEChERS-based method was optimized for the extraction of carbamate residues from a wide variety of fresh herbal products. The proposed method allowed recoveries higher than 72%, achieving quantification limits of 2µgkg(-1), therefore below maximum residue limits established for this type of samples. The combination of QuEChERS with UHPLC-MS/MS introduces a high-throughput methodology for the monitoring of these residues in this type of matrices scarcely explored. The analysis of the real samples revealed that several samples sold in the European Union and in the North West region of Cameroon contain pesticides in concentrations below the maximum residue limits.

Protective effect of Basella alba and Carpolobia alba extracts against maneb-induced male infertility.

CONTEXT: Male infertility is one of the leading causes of social frustration and marginalization, mainly in the developing world. It is attributed to many factors including exposure to agropesticides such as manganese ethylenebis (dithiocarbamate) (maneb), which is one of the most frequently used fungicides in Cameroon. Previous reports support efficiency of some medicinal plants commonly used in Cameroonian folk medicine for the treatment of this disorder. OBJECTIVE: The present study was aimed at assessing the protective effect of extracts from selected plant species, namely Basella alba L. (Basellaceae) (MEBa) and Carpolobia alba G. Don (Polygalaceae) (AECa), in alleviating the maneb-induced impairment of male reproductive function in Wistar albino rats. MATERIALS AND METHODS: The rats were treated with vehicle, plant extract (MEBa or AECa), maneb and maneb plus plant extract, respectively, and their fertility was assessed. Animals were thereafter sacrificed and organs (liver, kidneys and reproductive organs) were dissected out and weighed. Serum androgens together with alanine aminotransferase, liver glutathione and thiobarbituric acid reactive species (TBARS) were also measured. RESULTS AND DISCUSSION: From this study, both plant extracts stimulated testosterone and improved fertility. Administration of MEBa plus maneb prevented fertility reduction by maneb and minimized the inhibitory effect of maneb on testosterone levels. AECa also improved fertility of the maneb-exposed rats, though without restoring testosterone levels, and other investigated parameters remained unaffected by different treatments. CONCLUSION: These findings emphasized the beneficial effects of B. alba and C. alba extracts on male fertility, and suggest their protective effect against maneb-induced toxicity in male reproductive function.

Adverse effects of bisphenol A on male reproductive function.

BPA is a ubiquitous environmental contaminant, resulting mainly from manufacturing,use or disposal of plastics of which it is a component, and the degradation of industrial plastic-related wastes. Growing evidence from research on laboratory animals, wildlife, and humans supports the view that BPA produces an endocrine disrupting effect and adversely affects male reproductive function. To better understand the adverse effects caused by exposure to BPA, we performed an up-to-date literature review on the topic, with particular emphasis on in utero exposure, and associated effects on spermatogenesis, steroidogenesis, and accessory organs.BPA studies on experimental animals show that effects are generally more detrimental during in utero exposure, a critical developmental stage for the embryo. BPA has been found to produce several defects in the embryo, such as feminization of male fetuses, atrophy of the testes and epididymides, increased prostate size, shortening of AGD, disruption of BTB, and alteration of adult sperm parameters (e.g.,sperm count, motility, and density). BPA also affects embryo thyroid development.During the postnatal and pubertal periods and adulthood, BPA affects the hypothalamic-pituitary-testicular axis by modulating hormone (e.g., LH and FSH,androgen and estrogen) synthesis, expression and function of respective receptors(ER, AR). These effects alter sperm parameters. BPA also induces oxidative stress in the testis and epididymis, by inhibiting antioxidant enzymes and stimulating lipid peroxidation. This suggests that employing antioxidants may be a promising strategy to relieve BPA-induced disturbances.Epidemiological studies have also provided data indicating that BPA alters male reproductive function in humans. These investigations revealed that men occupationally exposed to BPA had high blood/urinary BPA levels, and abnormal semen parameters. BPA-exposed men also showed reduced libido and erectile ejaculatory difficulties; moreover, the overall BPA effects on male reproduction appear to be more harmful if exposure occurs in utero. The regulation of BPA and BPA-related products should be reinforced, particularly where exposure during the fetal period can occur. The current TDI for BPA is proposed as 25 and 50 1-1g/kg bwt/day (European Food Safety Authority and Health Canada, respectively). Based on the evidence available, we believe that a TDI value of 5 1-1g/kg bwt/day is more appropriate (the endpoint is modulation of rat testicular function). Certain BPA derivatives are being considered as alternatives to BPA. However, certain of these related products display adverse effects that are similar to those of BPA. These effects should be carefully considered before using them as final alternatives to BPA in plastic production.

Effect of agropesticides use on male reproductive function: a study on farmers in Djutitsa (Cameroon).

This study aimed at investigating the effect of agropesticides on male reproductive function in farmers in Djutitsa (West Cameroon). To this end, 47 farmers in Djutitsa were asked questions on their health status and pesticide use in agriculture. Thereafter, their blood samples were collected for assessment of sex hormones including serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), androstenedione, testosterone, as well as sex hormone binding globulin (SHBG). Their serum triiodothyronine (T3) and thyroxine (T4) levels were also measured. Thirty seven men not exposed to agropesticides were recruited as control group. Fifty six pesticides containing 25 active substances were currently used by farmers enrolled in our study, and most of their symptoms were related to spread/use of these chemicals. Compared to the control group, there was no significant difference in FSH, LH, SHBG, estradiol, and thyroid hormones (T3 and T4) levels. Farmers had significantly lower serum testosterone (20.93 ± 1.03 nM vs. 24.32 ± 1.32 nM; P < 0.05) and higher androstenedione level (3.83 ± 0.20 nM vs. 2.80 ± 0.15 nM; P < 0.001). Their serum free testosterone as well as bioavailable testosterone were unchanged, while estradiol/testosterone and androstenedione/testosterone ratios were significantly increased (0.45 ± 0.03% vs. 0.33 ± 0.02%; P < 0.01 and 12.26 ± 3.64 vs 19.31 ± 6.82; P < 0.001, respectively). Our results suggest that male farmers of Djutitsa (West Cameroon) are exposed to agropesticides due to improper protective tool, and this exposure may impair their reproductive function through inhibition of testosterone synthesis; probably by inhibition of testicular 17ß- hydroxysteroid dehydrogenase (17HSD3) and induction of aromatase (CYP19).

Effects of the methanol extract of Basella alba L (Basellaceae) on steroid production in Leydig cells.

In this study, Leydig cells were purified from 70 day-old Sprague Dawley male rats and incubated with 10 and 100 µg/mL of methanol extract of Basella alba (MEBa) for 4 hours followed by the evaluation of cell viability, steroid (testosterone and estradiol) production, and the level of aromatase mRNA. Results showed that MEBa did not affect Leydig cell viability. At the concentration of 10 µg/mL, MEBa significantly stimulated testosterone and estradiol production (p < 0.01 and p < 0.03, respectively), and enhanced aromatase mRNA level (p < 0.04). These observations suggest that MEBa directly stimulated testosterone, estradiol and aromatase mRNA levels in isolated Leydig cells.