Hepatotoxicity of titanium dioxide nanoparticles.

The food additive E171 (titanium dioxide, TiO2), is widely used in foods, pharmaceuticals and cosmetics. It is a fine white powder, with at least one third of its particles sized in the nanoparticulate (˂100 nm range, TiO2 NPs). The use of E171 is controversial as its relevant risk assessment has never been satisfactorily accomplished. In vitro and in vivo studies have shown dose-dependent toxicity in various organs including the liver. TiO2 NPs have been shown to induce inflammation, cell death and structural and functional changes within the liver. The toxicity of TiO2 NPs in experimental models varies between organs and according to their physiochemical characteristics and parameters such as dosage and route of administration. Among these factors, ingestion is the most significant exposure route, and the liver is a key target organ. The aim of this review is to highlight the reported adverse effects of orally administered TiO2 NPs on the liver and to discuss the controversial state of its toxicity.

Thunderstorm asthma: a review, risks for Aotearoa New Zealand, and health emergency management considerations.

AIM: To provide an up-to-date review of thunderstorm asthma (TA), identifying causative factors, and to discuss implications for management of TA in New Zealand. METHODS: A literature search was carried out to identify articles that investigate the characteristics and causative factors of TA. Nine electronic databases were searched, yielding 372 articles, reduced to 30 articles after screening for duplication and relevance. RESULTS: TA is globally rare, with 29 reported events since 1983, but is expected to increase in frequency as Earth warms. Triggers include both pollen (particularly ryegrass pollen) and fungal spores. Individual risk factors include outdoor exposure, sensitivity to triggering allergens and history of seasonal allergic rhinitis. History of asthma is not a strong risk factor but is associated with severity of outcome. Limited data on demographic characteristics suggests that individuals aged between 20 and 60 and (in Australasia) of Asian/Indian ethnicity are at higher risk. A single TA event has been reported in New Zealand to date, but much of New Zealand may be at risk of future events given that ryegrass pastures are widely distributed, and summer thunderstorms can occur anywhere. CONCLUSIONS: We recommend developing rapidly deployable public messaging to support the health emergency management response to future TA events, together with the instigation of routine aeroallergen monitoring.

Extension of the color suite available for chemical enhancement of fingerprints in blood.

The use of ortho- and para-phenylenediamine (OPD & PPD respectively) for the enhancement of fingerprints in blood has been investigated. Optimal pH conditions and H2O2 concentrations have been determined using UV/Vis spectroscopy. Both OPD and PPD are effective and less hazardous alternatives to the presently used 3,3'-diaminobenzidine (DAB) for the development of blood fingerprints, especially on porous surfaces. The orange color of OPD and the purple color of PPD offer alternative colors to the brown color of DAB and the light green color of ABTS for standing out against particular backgrounds. Both OPD and PPD can be used after ninhydrin treatment, but the reverse is not the case.