Toxicological response of Sprague Dawley rats from inhalation exposure to perfluorooctane sulfonyl fluoride (POSF).

Perfluorooctane sulfonyl fluoride (POSF) was a volatile starting material in the production of perfluorooctane sulfonate (PFOS), a stable surfactant that has been extensively studied due to its ubiquitous environmental distribution and slow clearance in humans. Because the inhalation toxicity of POSF on repeated exposure has not been previously reported, the current study evaluated the inhalation toxicity of POSF at 30, 100, and 300ppm (v/v) in rats for up to 13 weeks with a four-week recovery period. The extent of PFOS formation was also measured because POSF hydrolyzed to form PFOS. In addition, detailed urinalysis and examination of the urinary bladder were included to determine if factors associated with the development of bladder cancer were present. Exposure to POSF at 300ppm was associated with reduction in body weight-gain, necrosis of laryngeal cartilage, increased lung and bronchi weight with septal thickening, and changes in alveolar macrophages. The microscopic observations in larynx and lung are consistent with likely hydrolysis of POSF to form hydrogen fluoride (HF). Exposure to POSF at 100 and 300ppm was associated with increased relative liver weight, hepatocellular hypertrophy (except for females exposed to 100ppm POSF), and lowering of serum cholesterol (male only). After 13 weeks of exposure to 30, 100, or 300ppm POSF, serum PFOS concentration approximated 7, 35, or 100µg/mL, respectively. Approximately 0.1% of inhaled POSF was converted to PFOS. No changes indicative of bladder effects were observed in these rats exposed to POSF at any dose.

Occupational Hydrofluoric Acid Injury from Car and Truck Washing--Washington State, 2001-2013.

Exposure to hydrofluoric acid (HF) causes corrosive chemical burns and potentially fatal systemic toxicity. Car and truck wash cleaning products, rust removers, and aluminum brighteners often contain HF because it is efficient in breaking down roadway matter. The death of a truck wash worker from ingestion of an HF-based wash product and 48 occupational HF burn cases associated with car and truck washing in Washington State during 2001-2013 are summarized in this report. Among seven hospitalized workers, two required surgery, and all but one worker returned to the job. Among 48 injured workers, job titles were primarily auto detailer, car wash worker, truck wash worker, and truck driver. Because HF exposure can result in potentially severe health outcomes, efforts to identify less hazardous alternatives to HF-based industrial wash products are warranted.

Methods, setup and safe handling for anhydrous hydrogen fluoride cleavage in Boc solid-phase peptide synthesis.

Solid-phase peptide synthesis (SPPS) using tert-butyloxycarbonyl (Boc)/benzyl (Bzl) chemistry is an indispensable technique in many laboratories around the globe, and it provides peptides to the pharmaceutical industry and to thousands of scientists working in basic research. The Boc/Bzl strategy has several advantages, including reliability in the synthesis of long and difficult polypeptides, alternative orthogonality regarding protecting groups and ease of producing C-terminal thioesters for native chemical ligation applications. In this process, anhydrous hydrogen fluoride (HF) is used to remove the side chain protecting groups of the assembled peptide and to release the peptide from the resin, a process typically described as 'HF cleavage'. This protocol describes the general methodology, apparatus setup and safe handling of HF, with the aim of providing comprehensive information on the safe use of this valuable, well-studied and validated cleavage technique. We explain the cleavage mechanism, the physicochemical properties and risks of HF, first aid measures and the correct use of the apparatus. In addition, we provide advice on scavenger selection, as well as a troubleshooting section and video material illustrating key steps of the procedure. The protocol comprises precleavage sample preparation (30 min-2.5 h), complete HF cleavage procedure (2 h) and reaction workup (30 min).

Acute hydrofluoric acid exposure reported to Taiwan Poison Control Center, 1991-2010.

BACKGROUND: Hydrofluoric acid (HF) is a dangerous chemical that can cause severe cutaneous burns as well as possible systemic toxicity. METHODS: We retrospectively analyzed all human HF exposure cases reported to the National Poison Control Center of Taiwan between 1991 and 2010. RESULTS: In this 20-year survey, 324 calls were identified, with a majority of dermal exposure (84%). Occupational exposure accounted for 80% of all cases, with workers in semiconductor industry (61%), cleaning industry (15%), chemical or metal industry (13%), and other industries (11%). Electrolyte imbalances were uncommon, hypocalcemia, hypomagnesemia, and hypokalemia were recorded in 8.6%, 1.2%, and 1.5% of all cases, respectively. Most cases (64%) of dermal exposure received antidotal treatment. Treatment modalities of dermal exposure included calcium gluconate soaking, 49.8%; intravenous calcium, 20.6%; and topical use of calcium gluconate gel, 13.9%. Twenty patients (7%) received surgery. Following HF exposure, the majority of patients presented with mild (56.5%) or moderate (36.7%) toxic effects. However, four patients were severely intoxicated; two patients died of HF-related dysrhythmia and shock. CONCLUSIONS: Significant symptomology may occur following HF exposure, and most of the HF exposure required hospitals evaluation. Calcium gluconate soaks appear to be effective in reducing local pain and tissue damage. Hyperkalemia should not be overemphasized as a common finding in HF exposure, hypokalemia tends to occur in cases of severe HF poisoning.

Finger burns caused by concentrated hydrofluoric acid, treated with intra-arterial calcium gluconate infusion: case report / Queimadura digital por ácido fluorídrico concentrado tratada com infusão intra-arterial de gluconato de cálcio: relato de caso

CONTEXT: Hydrofluoric acid (HF) is widely used in industry and at home. Severe lesions can occur after contact with highly concentrated solutions, leading to tissue necrosis and bone destruction. Specific treatment is based on neutralization of fluoride ions with calcium or magnesium solutions. CASE REPORT: A 41-year-old male was seen at the emergency department 35 minutes after skin contact with 70 percent HF, showing whitened swollen lesions on the middle and fourth fingers of his right hand with severe pain starting immediately after contact. 2.5 percent calcium gluconate ointment was applied. Twenty-four hours later, the patient was still in severe pain and the lesions had worsened. Considering the high concentration of the solution, early start of severe pain, lesion characteristics and impossibility of administering calcium gluconate subcutaneously because of the lesion location, the radial artery was catheterized and 2 percent calcium gluconate was administered via infusion pump for 36 hours, until the pain subsided. No adverse effects were seen during the procedure. Ten days later, the lesions were stable, without bone abnormalities on X-rays. Six months later, a complete recovery was seen. CONCLUSIONS: Intra-arterial calcium gluconate might be considered for finger burns caused by concentrated HF. Complete recovery of wounded fingers can be achieved with this technique even if started 24 hours after the exposure. However, controlled clinical trials are needed to confirm the effectiveness and safety of this intervention.

CONTEXTO: Ácido fluorídrico é largamente usado na indústria e no ambiente doméstico. Lesões graves podem ocorrer depois de contato com soluções altamente concentradas levando a necrose tecidual e destruição óssea. O tratamento específico é baseado na neutralização dos íons de flúor com soluções de cálcio ou magnésio. RELATO DE CASO: Homem de 41 anos foi atendido na sala de urgência 35 minutos depois de contato da pele com ácido fluorídrico a 70 por cento, apresentando lesões esbranquiçadas e edemaciadas nos dedos médio e quarto da mão direita com dor intensa que iniciou logo após o contato. Pomada de gluconato de cálcio a 2,5 por cento foi aplicada. Depois de 24 horas, o paciente continuava com dor mais intensa e as lesões haviam piorado. Considerando a concentração da solução, o início precoce da dor intensa, as características das lesões e a impossibilidade de administrar gluconato de cálcio no subcutâneo devido ao local da lesão, foi inserido cateter na artéria radial para infusão de gluconato de cálcio a 2 por cento com bomba de infusão por 36 horas até melhora da dor. Nenhum efeito adverso foi observado durante o procedimento. Dez dias depois as lesões encontravam-se estáveis, sem alterações dos ossos vistas nos raios-X. Seis meses depois houve recuperação completa. CONCLUSÃO: Gluconato de cálcio intra-arterial pode ser considerado em queimaduras digitais por ácido fluorídrico. Recuperação completa dos dedos acometidos pode ser obtida com essa técnica mesmo que iniciada 24 horas após a exposição. Porém, ensaios clínicos controlados são necessários para confirmar a efetividade e a segurança desta intervenção.

Hydrofluoric acid inhalation injury.

Hydrofluoric acid has a unique mechanism for causing devastating injuries when it contacts human tissue. Although a great deal of literature exists for cutaneous exposures, inhalational exposures have not been as well studied. Although most cases of severe inhalational exposures to hydrofluoric acid are rapidly lethal, here we present a case of a patient who presented with a severe inhalation injury who survived. This case highlights the extreme complexity of managing this kind of injury and the need for more experimental research to develop better treatment options.

Hydrofluoric acid burns.

OBJECTIVE: The purpose of this article is to report our experience with hydrofluoric acid (HF) burns and to present our management guidelines for these burns, which include a novel way of delivering calcium combined with dimethyl sulphoxide (DMSO) for cutaneous burns. METHOD: We reviewed our institutional experience from 1977 to 1999 for patients presenting with burns caused by hydrofluoric acid and collected data on age, sex, burn size, anatomical site, method of contact, surgical procedure, and outcome. RESULTS: Of a total of 2310 admissions, 42 HF burns patients were identified during the study period. The average age was 34 years. There were 35 males and 7 females. Seventy-four percent of cases received burns to the upper limb. Median burn size was 1% of the total body surface area. Seventeen percent of patients required a surgical procedure. In 24% of cases, the method of contact was work related and 40% were injured using cleaning products at home or on boats. No deaths were recorded. CONCLUSION: HF injury is uncommon but problematic burns often requiring surgery. RECOMMENDED MANAGEMENT: In cases of cutaneous exposure, treatment should commence immediately with 30 min lavage followed by application dimethyl sulphoxide 50% + calcium gluconate 10% in surgical jelly. If hand or forearm is affected, regional intravenous calcium 'Bier's block' using 40 ml 10% calcium gluconate with 5000 U heparin in total final volume of 40 ml may be indicated. Subcutaneous infiltration may be indicated for elsewhere at 0.5 ml/cm(2) burn of 10% calcium gluconate. Persisting pain may require nail removal or arterial calcium infusion.

Short-term effects of hydrogen fluoride on Nicotiana tabacum L.

Data on the short-term effects of fumigation with hydrogen fluoride (HF) on the response behavior of the Nicotiana tabacum L. cv. St. Karabalar 6265 are being presented. Growth rate, fluoride accumulation in leaves and soils, and degradation in chlorophyll and nicotine contents of the plant species against the variations in two experimental factors, namely the exposure concentration and exposure time parameters, were investigated. Resulting data reveals that the variety selected for this study is not so tolerant to fluoride as generally reported in the literature, if only the individual effects of the pollutant is considered.

Fluoride-induced interleukin-6 and interleukin-8 synthesis in human epithelial lung cells.

Exposure to fluorides has been associated with asthmatic symptoms among workers in the aluminium industry. In a recent experimental study hydrogen fluoride (HF) was found to induce a weak inflammatory response in humans. In the present study the potential of sodium fluoride (NaF) and HF to induce cytokine response was examined and how these responses are modulated by Al3+ in a human epithelial lung cell line (A549). Dose-response experiments showed a maximal release of IL-6 and IL-8 at a concentration of 5 mM NaF 24 h after addition. The responses to HF were of a similar magnitude as for NaF. Time-course experiments showed a NaF-induced IL-6 response at 5 h, whereas an IL-8 response was observed after 10 h. Cycloheximide treatment completely abolished the NaF-induced cytokine responses. A marked increase in the mRNA level for IL-6 was observed already 2 h after exposure to 5 mM NaF, and presumably is a prerequisite for the subsequent increase of IL-6. The fluoride-induced effects on IL-6 and IL-8 release were strongly reduced by pretreatment with deferoxamine (an Al3+-chelator), and enhanced by addition of Al3+. This indicates that an AlF4-- complex, a known activator of GTP-binding proteins, is involved in fluoride-induced IL-6 and IL-8 responses in A549 cells.

[Effect of the combined action of hydrogen fluoride and phosphine on the structural and functional properties of the sarcoplasmic reticulum membranes of the myocardium with nutrition of varying character]. / Vliianie kombinirovannogo deistviia ftoristogo vodoroda i fosfina na strukturno-funktsional'nye svoistva membran sarkoplazmaticheskogo retikuluma miokarda v usloviiakh raznokharakternogo pitaniia.

A study was made of the activity of transport ATPases of rat myocardial sarcoplasmic reticulum membranes under the conditions of different-character nutrition and under the action of hydrogen fluoride and phosphine. The combined effect of the gases under study was accompanied by activation of Ca2+ ATPase and total ATPase. The character of nutrition, the degree of its adequacy according to retinol, tocopherol, ascorbic acid and essential amino acids (lysine, methionine, and threonine) determined not only the activity of transport ATPases and the phospholipid content of sarcoplasmic reticulum membranes but also the features of the toxic effects of hydrogen fluoride and phosphine. The enrichment of the diet with retinol, tocopherol, ascorbic acid and thiamine reduces the toxic effects of these gases under the conditions of acute and chronic priming as well.