Exposure to particulate hexavalent chromium exacerbates allergic asthma pathology

Abstract

Airborne hexavalent chromate, Cr(VI), has been identified by the Environmental Protection Agency as a possible health threat in urban areas, due to the carcinogenic potential of some of its forms. Particulate chromates are produced in many different industrial settings, with high levels of aerosolized forms historically documented. Along with an increased risk of lung cancer, a high incidence of allergic asthma has been reported in workers exposed to certain inhaled particulate Cr(VI) compounds. However, a direct causal association between Cr(VI) and allergic asthma has not been established. We recently showed that inhaled particulate Cr(VI) induces an innate neutrophilic inflammatory response in BALB/c mice. In the current studies we investigated how the inflammation induced by inhaled particulate Cr(VI) might alter the pathology of an allergic asthmatic response. We used a well-established mouse model of allergic asthma. Groups of ovalbumin protein (OVA)-primed mice were challenged either with OVA alone, or with a combination of OVA and particulate zinc chromate, and various parameters associated with asthmatic responses were measured. Co-exposure to particulate Cr(VI) and OVA mediated a mixed form of asthma in which both eosinophils and neutrophils are present in airways, tissue pathology is markedly exacerbated, and airway hyperresponsiveness is significantly increased. Taken together these findings suggest that inhalation of particulate forms of Cr(VI) may augment the severity of ongoing allergic asthma, as well as alter its phenotype. Such findings may have implications for asthmatics in settings in which airborne particulate Cr(VI) compounds are present at high levels.

Intranasal Chromium Induces Acute Brain and Lung Injuries in Rats: Assessment of Different Potential Hazardous Effects of Environmental and Occupational Exposure to Chromium and Introduction of a Novel Pharmacological and Toxicological Animal Model

“…Moreover, the revealed foreign body granuloma that were only demonstrated in inPDC (2 mg/kg) are in complete agreement with Toya et al [23] who demonstrated alveolar and interstitial inflammation and granuloma formation in rats upon intratracheal instillation of chromate compound. These granuloma could be explained by the irritation induced by chromium which is well known as respiratory and mucous irritant [45]. …”

Effect of Simvastatin on Sodium Dichromate-Induced Lung Injury in Rats

“…Cr(VI) at doses of 8, 12, and 16 mg/kg BW/day, respectively, for eight consecutive days. Groups four, six, and eight were pretreated with SIMV (20 mg/kg BW via oral gavage) 30 minutes prior to administration of Cr(VI) (8,12, and 16 mg/kg BW, respectively) for eight consecutive days.…”

“…Exposure to Cr(VI) has induced pulmonary injuries in humans and animals (6,(10)(11)(12)(13). Asatiani et al (2011) reported that Cr(VI) can impair the antioxidant defense system (14).…”

Scientific Opinion on the safety and efficacy of vitamin K3 (menadione sodium bisulphite and menadione nicotinamide bisulphite) as a feed additive for all animal species

“…Potassium dichromate was found to be the most frequent allergen among 20 common allergens (Geier et al, 2011). Exposure by inhalation to Cr(VI) dust exacerbates allergic asthma (Schneider et al, 2012). Owing to the presence of Cr(VI), the possibility of allergic reactions cannot be ruled out.…”