20 ADVERSE HEALTH EFFECTS CAUSED BY PARAQUAT | February 2017
concentrations of the substance and/or significant delay in treatment initiation. The exact efficacy of the current medical management remains controversial. Therefore, it is crucial for emergency physicians to suspect paraquat poisoning when facing chemical burns and skin lesions and to investigate for the possibility of intoxication, particularly when skin lesions are associated with systemic symptoms.” [pp. 375-376] Tungsana, Chusilp et al 1983 – Acute poisoning after skin exposure to paraquat (Thailand)52 “Dermal exposure to paraquat, especially to the scrotum may produce serious systemic toxicity. [...] We present here a patient who developed a skin lesion and hepatic, renal and pulmonary injury following paraquat exposure to the perineum. The systemic toxicity was perhaps mild and unrecognized until 3 weeks later when blood chemistry was obtained. Although sepsis can mediate acute renal and respiratory failure, there was no fever or other clinical evidence of toxaemia. The failure to detect paraquat in blood and urine was not surprising so long after exposure. [...] In spite of the short exposure time, a concentrated preparation of paraquat was used, and the soft and highly vascular scrotal skin might allow significant absorption to produce systemic effects. This report adds to the literature on the potential hazards of exposure of normal skin to paraquat. Systemic effects are not common, but may occur especially when a concentrated solution contacts scrotal skin.” Zhou, Kan et al 2013 – Paraquat poisoning by skin absorption: Two case reports (China)53 “The present report describes two cases of paraquat poisoning by skin absorption. The cases involved contractual workers who were spraying paraquat in an orchard. Whilst spraying, some solution adhered to their skin. The skin developed erythema followed by blistering and hemorrhaging hemorrhagic diabrosis. Six days later the patients were admitted to the Department of Poisoning and Occupational Disease, Qilu Hospital of Shandong University (Jinan, China) with 3 and 2 % total body surface area (TBSA) burns, respectively. […] paraquat may be absorbed through skin injuries, and since 1978 there have been several reported cases of severe paraquat poisoning by this pathway (Newhouse et al 1978; Bismuth et al 1982; Tungsanga 1983; Gear 2001). Since the beginning of its widespread use in 2000, acute paraquat poisoning has continued to be a major public health problem in the rural areas of China, normally from deliberate ingestion or accidental exposure (Ruan 2009). To the best of our knowledge, these instances are rare in China. […] paraquat poisoning remains a severe health problem globally and the degree of the severity depends on the exposure route and dose. […] There has been a recent rise in case reports regarding paraquat poisoning following dermal exposure (Soloukides et al 2007; Peiró et al 2007; Lin et al 2003). In the two cases documented in this case report, the high temperature and humidity together with the lack of protection for the sprayers increased the risk of dermal exposure. In Case 1, the paraquat entered the body through the damaged skin and caused renal injury and pulmonary fibrosis. In Case 2, the paraquat caused serious skin injuries similar to that of Case 1. […] These cases suggest that paraquat is well absorbed through abraded or injured skin and may result in severe toxicity.”
1.4 – EYE INJURY AND IMPAIRED SIGHT Adams et al 2013 – Eye injury from pesticides common in the UK; paraquat third-most frequent cause54 “6036 unintentional pesticide exposures were reported during the period [April 2004 to April 2012 in the UK]; 673 (11.1 %) of these cases involved eye contact. In 475 of these exposures eye contact was the only route of exposure. Five hundred and sixty-six (84.1 %) exposures involved adults; 103 children; 4 ages unknown. In 246 (36.6 %) exposures no symptoms were reported; 379 (56.3 %) reported eye irritation; 52 conjunctivitis; 45 eye burn; 34 abnormal vision; 35 lacrimation. The most common agent classes involved were: herbicides (265); insecticides (212); wood preservatives (83); sheep dip (37); fungicide (28); surface biocide (20); rodenticide (18); fumigant (4) and anti-fouling products (4). In 430 (63.9 %) exposures the pesticide was in use by the patient; 52 by another person; 59 exposures occurred after application; 64 due to unsatisfactory storage. One hundred and fifty-three exposures were occupational. Of the 566 adults: 62 (11 %) patients reported being exposed during windy conditions; 42 (7.4 %) reported hand-to-eye contamination; 13 reported using no eye protection. Five were exposed despite use of eye protection. [...] For exposures graded “moderate” the most common agents were: cresol/phenol (7); glyphosate (5); paraquat (5); tetramethrin (4); diquat (4); 2,4-D (4). [...] Eye contact with pesticides is a common route of pesticide exposure (11.1 %). Exposures frequently occur during patient use (63.9 %) and may result in moderate symptoms such as corneal burns (57, 12 %).” Fernando & Perera 2011 – Severe eye injury from splash of paraquat (Malaysia)55 “We report a case of severe eye injury from paraquat to emphasize the need for proper and timely management. […] The eye was washed immediately but she developed irritation, burning sensation and pain which became severe over the next few days. When she presented on the fourth day, she had ptosis and complained of poor vision, severe pain and difficulty in opening the eye. Her visual acuity was confined to hand movements. The conjunctiva was heavily oedematous and hyperaemic. Fluorescein staining revealed a large epithelial defect covering almost entire cornea. The anterior chamber showed a low-grade uveitis […] A chemical injury therapeutic regime was commenced. […] On the fifth day of treatment, she had no ptosis, no pain, the conjunctiva was minimally hyperaemic and the limbal ischaemia had reduced. On the 12th day the visual acuity of the eye was 6/6. There were no signs of eye injury. Timely and appropriate intervention can bring excellent recovery from paraquat eye injury as shown in this case.” Liu et al 2012 – Ocular burns caused by paraquat require hospitalization (China)56 “From June 2008 to Seprember 2010, 5 paraquat-induced eye burn patients were admitted in our hospital. The patients were treated with fist aid irrigation, eyedrops of heparin, antibiotics and own serum, ointment of rb-bFGF. Pseudomembrane of conjunctiva was separated. Amniotic membrane transplantation was given to a serious patient. […] Paraquat-induced ocular burn patients have clinical characteristics of conjunctiva Pseu-