Chlorothalonil, a possible cause of erythema dyschromicum perstans (ashy dermatitis)

The toxicity and health risk of chlorothalonil to non-target animals and humans: A systematic review

Chlorothalonil (CTL), an organochloride fungicide applied for decades worldwide, has been found to be present in various matrixes and even accumulates in humans or other mammals through the food chain. Its high residue and diffusion in the environment have severely affected food security and public health. More and more research has considered CTL as a possible toxin to environmental non-target organisms, via influencing multiple systems such as metabolic, developmental, endocrine, genetic, and reproductive pathways. Aquatic organisms and amphibians are the most vulnerable species to CTL exposure, especially during the early period of development. Under experimental conditions, CTL can also have toxic effects on rodents and other non-target organisms. As for humans, CTL exposure is most often reported to be relevant to allergic reactions to the skin and eyes. We hope that this review will improve our understanding of the hazards and risks that CTL poses to non-target organisms and find a strategy for rational use.

Detection of the fungicide transformation product 4-hydroxychlorothalonil in serum of pregnant women from Sweden and Costa Rica

BACKGROUND

4-hydroxychlorothalonil (HCT, R182281), a transformation product of the fungicide chlorothalonil, was recently identified in human serum and breast milk. There are indications that HCT may be more toxic and environmentally persistent than chlorothalonil.

OBJECTIVE

Our aim was to investigate serum concentrations of HCT in pregnant women in Sweden and Costa Rica.

METHODS

We developed a quantitative analytical method for HCT using liquid chromatography tandem mass spectrometry. We measured HCT in 1808 serum samples from pregnant women from the general population in Sweden (1997-2015) and in 632 samples from 393 pregnant women from an agricultural population in Costa Rica (2010-2011). In Swedish samples, we assessed time trends and investigated seasonality. In the Costa Rican samples, we evaluated variability between and within women and explanatory variables of HCT concentrations.

RESULTS

HCT was detected in all serum samples, and the limit of detection was 0.1 µg/L. The median HCT concentration in the Swedish samples was 4.1 µg/L (interquartile range [IQR] of 2.9 - 5.8 µg/L), and 3.9 times higher in the Costa Rican samples (median: 16.1 µg/L; IQR: 10.6 - 25.0 µg/L). We found clear seasonal variation with higher concentrations in the first half of each year among Swedish women. In the Costa Rican study, women working in agriculture and living near banana plantations had higher HCT concentrations, whilst higher parity and having a partner working in agriculture were associated with decreased HCT, and no clear seasonal pattern was observed.

IMPACT STATEMENT

For the first time, this study quantifies human exposure to the fungicide chlorothalonil and/or its transformation product 4-hydroxychlorothalonil (HCT, R182281) and finds higher serum concentrations in women from a tropical agricultural setting as compared with women from the general population in Sweden.

Erythema Dyschromicum Perstans After Adalimumab Treatment

Tumor necrosis factor (TNF) is a cytokine that regulates immunity by binding to the cytokine receptor (TNFR), which has a role in treating inflammatory, neoplastic, and autoimmune diseases. Medications, including etanercept, infliximab, and adalimumab, are examples of TNF-alpha blockers. Adalimumab is a fully human immunoglobulin monoclonal antibody approved for use in the treatment of psoriasis, psoriatic arthritis, rheumatoid arthritis, inflammatory bowel disease, and hidradenitis suppurativa according to the American College of Rheumatology. However, there are few reports of cases where its administration was associated with skin reactions. In the present paper, we report a case of a psoriatic male patient who developed a cutaneous reaction of the face following treatment with adalimumab.

Health Symptoms Related to Pesticide Use in Farmers and Laborers of Ecological and Conventional Banana Plantations in Ecuador

Conventional banana farming is pesticide-intensive and leads to high exposure of farmworkers. Ecuador is the world’s biggest exporter of bananas. In this field study in 5 communities in Ecuador, we recorded potentially pesticide-associated subjective health symptoms in farmworkers and compared pesticide users to workers in organic farming. With one exception, symptom rates were always higher in the pesticide-exposed group. Significance was reached in 8 out of 19 investigated symptoms with the highest odds ratios (and smallest p-values) for local irritation like skin and eye irritation (OR = 3.58, CI 1.10–11.71, and 4.10, CI 1.37–12.31, respectively) as well as systemic symptoms like dizziness (OR = 4.80, CI 1.55–14.87) and fatigue (OR = 4.96, CI 1.65–14.88). Moreover, gastrointestinal symptoms were reported more frequently by pesticide users: nausea (OR = 7.5, CI 1.77–31.77) and diarrhea (OR = 6.43, CI 1.06–30.00). The majority of farmworkers were not adequately protected from pesticide exposure. For example, only 3 of 31 farmworkers that had used pesticides recently reported using gloves and only 6 reported using masks during active spraying. Improved safety measures and a reduction in pesticide use are necessary to protect the health of banana farmworkers.

A global consensus statement on ashy dermatosis, erythema dyschromicum perstans, lichen planus pigmentosus, idiopathic eruptive macular pigmentation, and Riehl's melanosis

Ashy dermatosis (AD), lichen planus pigmentosus (LPP), erythema dyschromicum perstans (EDP), and idiopathic eruptive macular pigmentation are several acquired macular hyperpigmentation disorders of uncertain etiology described in literature. Most of the published studies on these disorders are not exactly comparable, as there are no clear definitions and different regions in the world describe similar conditions under different names. A consensus on the terminology of various morphologies of acquired macular pigmentation of uncertain etiology was a long-felt need. Several meetings of pigmentary disorders experts were held to address this problem. A consensus was reached after several meetings and collation of e-mailed questionnaire responses and e-mail communications among the authors of publications on the above conditions. This was achieved by a global consensus forum on AD, LPP, and EDP, established after the 22nd International Pigment Cell Conference held in Singapore in 2014. Thirty-nine experts representing 18 countries participated in the deliberations. The main focus of the deliberations was terminology of the conditions; as such, we present here the consensus statement of the forum and briefly review the available literature on the subject. We have not attempted to discuss treatment modalities in detail.

Reversible Acute Kidney Injury Associated with Chlorothalonil Ingestion

A 43-year-old man ingested a chlorothalonil-containing fungicide in a suicide attempt. The patient was found to have acute kidney injury from acute tubular necrosis on hospital admission (serum creatinine 2.9 mg/dL), although his renal function recovered with hydration and supportive care. Acute toxicity from chlorothalonil ingestion has been described very rarely, and no previous cases have described clinically-significant renal effects.

Ashy dermatosis in an 8-year-old Indian child

Ashy dermatosis is a disorder of pigmentation, characterized by asymptomatic symmetric ashy gray-colored macules, in the first to third decade of life. It can, however, affect children sometime. But, there is a paucity of similar cases in Indian children. We present a case of ashy dermatosis in an 8-year-old Indian girl who presented to skin OPD with areas of ashy pigmentation, which were distributed symmetrically. Skin biopsy was consistent with lichenoid pattern histology. This case has been reported to highlight the rarity of ashy dermatosis in Indian children.

Pesticides use by smallholder farmers in vegetable production in Northern Tanzania

Small-scale farmers in Northern Tanzania grow vegetables that include tomatoes, cabbages and onions and use many types of pesticides to control pests and diseases that attack these crops. Based on the use of questionnaires and interviews that were conducted in Arumeru, Monduli, Karatu, and Moshi rural districts, this study investigates farmers' practices on vegetable pest management using pesticides and related cost and health effects. The types of pesticides used by the farmers in the study areas were insecticides (59%), fungicides (29%) and herbicides (10%) with the remaining 2% being rodenticides. About a third of the farmers applied pesticides in mixtures. Up to 90% had a maximum of 3 pesticides in a mixture. In all cases there were no specific instructions either from the labels or extension workers regarding these tank mixtures. Fifty three percent of the farmers reported that the trend of pesticide use was increasing, while 33% was constant and 14% was decreasing. More than 50 percent of the respondents applied pesticides up to 5 times or more per cropping season depending on the crop. Insecticides and fungicides were routinely applied by 77% and 7%, respectively by these farmers. Sixty eight percent of farmers reported having felt sick after routine application of pesticides. Pesticide-related health symptoms that were associated with pesticides use included skin problems and neurological system disturbances (dizziness, headache). Sixty one percent of farmers reported spending no money on health due to pesticides. These results can be used to develop a tool to quantify the cost of pesticide use in pest management by small-scale vegetable farmers in Northern Tanzania and contribute to the reformation of pesticide policy for safe and effective use of pesticides.

Airborne irritant contact dermatitis and conjunctivitis after occupational exposure to chlorothalonil in textiles

Chlorothalonil (tetrachloro-1,3-benzenedicarbonitrile, CAS 1897-45-6) is a pesticide that has been on the market for many years. It is used as a fungicide in agriculture, horticulture, and floriculture; as a wood preservative; and in paint. We report an epidemic of airborne irritant contact dermatitis, conjunctivitis, and upper airway complaints among seamstresses in a Portuguese trailer tent factory, which we attribute to chlorothalonil. All exposed workers had work-related skin symptoms. After patch testing, we showed that none of these were of allergic origin. Instead of allergic reactions, we noticed a delayed type of irritation after 72 hr to chlorothalonil and to the textile extracts containing high concentrations of chlorothalonil. Although allergic and irritant contact dermatitis from chlorothalonil has been described before, this is, as far as we know, the first time that a delayed type of dermatitis, conjunctivitis, and upper airway irritation after exposure to chlorothalonil in tent-cloth is described.

Immunopathologic study of erythema dyschromicum perstans (ashy dermatosis)

Erythema dyschromicum perstans (EDP) is a pigmentary disease of unknown etiology in which damage to basal cells is thought to be mediated by adhesion molecules. The aim of this study was to characterize the histopathology and immunopathology of EDP. Forty-three patients from Medellín, Colombia, with the diagnosis of EDP were evaluated. Skin biopsy specimens were obtained for histopathology and immunohistochemistry, using monoclonal antibodies directed against the following markers: CD4, CD8, CD56, CD1a, CD68, CLA, HLA-DR, ICAM-1 and LFA-1alpha. A dermal lymphocytic infiltrate was observed in all cases, with a perivascular location in 86%. Other histologic features included melanophages in all specimens, vacuolization of the basement membrane zone (BMZ) 58% and exocytosis of lymphocytes (53.5%). The mean number of total leukocytes was 1510 cells mm-2 of tissue. There was a predominance of CD8+ T lymphocytes in the dermis and HLA-DR+, ICAM-1+ keratinocytes in the epidermis. Exocytosis of cutaneous lymphocyte antigen (CLA)+cells was observed in areas of BMZ damage, suggesting that response to antigenic stimulation may play a role in the development of EDP.

Erythema dyschromicum perstans in children: a report of 14 cases

BACKGROUND

Erythema dyschromicum perstans (EDP) or ashy dermatosis is a peculiar, slowly progressive, macular hyperpigmentation, which leaves a permanent discoloration. It is an acquired dermatosis that occurs most frequently in Central and South America. EDP usually appears in adults, but some isolated cases and small series have been reported in prepubertal children.

METHODS

A retrospective review of cases of EDP in 10-year-old children or younger, attended in a pediatric hospital between 1990 and 2003.

RESULTS

We present 14 cases of EDC in children 10 years and younger. With an additional 25 cases reported so far in the English language literature, a total of 39 children have been described. Unlike adult patients, who are most commonly of Hispanic origin, children with EDP are usually Caucasian. Other important facts in children with EDP are the absence of consistent trigger factors and an eventual improvement or resolution of the lesions in 50% of prepubertal patients.

CONCLUSION

We suggest that EDP is a distinctive clinical entity, different from lichen planus and lichen planus pigmentosus, which may be identical to the so-called idiopathic eruptive macular pigmentation.

Cutaneous diseases in Latinos

The knowledge of many specific skin diseases that predominantly affect Latinos has been increasing; however, the understanding of common skin disease in Latinos is superficial. There are few prospective studies done in the Latino population and none that differentiate between diverse Latino backgrounds. In view of the expanding Latino population in this country, such research is timely.

Erythema dyschromicum perstans in prepubertal children

Erythema dyschromicum perstans (EDP) is a rare disorder of pigmentation that is most common in Hispanic patients. In adults, EDP has a slow onset and is unlikely to resolve spontaneously. The etiology and clinical course in children is poorly defined. Physical examinations, chart reviews, and telephone interviews were performed for eight pediatric patients with EDP who were followed at Children's Memorial Hospital in Chicago between 1990 and 1998. All the patients available for long-term follow-up (five of the eight) experienced complete clearance without recurrence in an average of 2.5 years. In all of our patients, the onset was noted from July to December. The administration of aminopenicillins was coincident with the development of EDP in two of the patients. Review of the English-language literature reveals that 25 prepubertal children have previously been reported. Including our patients, 69% of prepubertal children with EDP experienced resolution. We concluded that the clinical course of childhood (prepubertal) EDP differs from that of adult EDP, and it is more likely to resolve within 2-3 years.

The diagnostic evaluation, treatment, and prevention of allergic contact dermatitis in the new millennium

Identifying the etiology of allergic contact dermatitis is a rewarding yet challenging endeavor. Not all allergic contact reactions are eczematous in appearance. The most reliable clinical clue to the allergic nature of the dermatitis is its geographic distribution. Once a list of culprit allergens has been identified by patch testing, the practitioner must identify the relevant allergen(s) and counsel the patient in avoidance. For most individuals, allergen avoidance results in resolution of the dermatitis; however, some patients will require continuing symptomatic therapy despite avoidance. For those patients unable to avoid known allergens, immunosuppressant therapies (including phototherapy) or barriers can be beneficial. Currently, hyposensitization is not a viable alternative for the treatment of allergic contact dermatitis.

Agricultural pesticide use in developing countries: health effects and research needs

Large worker populations in the Third World are exposed to increasing amounts of pesticides, including pesticides severely restricted and banned in industrialized countries. Studies on knowledge, attitudes, and practices indicate that unsafe use of pesticides is the rule in Third World countries. Surveys of acute poisonings show high rates in these countries, despite underregistration. The scarce studies on chronic health outcomes demonstrate neurotoxic, reproductive, and dermatologic effects. Exposure assessment consists mainly of cholinesterase testing, and few studies have quantified dermal and respiratory exposure. The few intervention studies demonstrate the need for evaluation of the impact of preventive measures and policies. There is no evidence that widespread "safe-use" programs have greatly affected exposure and morbidity. It was concluded that research should focus on simple methods for surveillance of exposure and on surveillance of acute illness and its causes in order to develop and evaluate rapid local interventions. Studies on chronic effects should be carried out in selected countries, aiming at long-term and broader interventions. Policies that promote the use of pesticides should be critically evaluated. North-South and South-South research collaborations must be encouraged to address this global health problem.