Electron microscopy of particles deposited in the lungs of nickel refinery workers

Occupational Medicine and Environmental Health in the Border Areas of Euro-Arctic Barents Region: A Review of 30-Year Russian-Norwegian Research Collaboration Outcomes

This year marks 30 years of close collaboration between a consortium of institutions, namely, the Northwest Public Health Research Center, Saint-Petersburg (NWPHRC); the Institute of Community Medicine (ICM) of UiT (The Arctic University of Norway, Tromsø); the National Institute of Occupational Health (NIOH), Oslo; the University Hospital of Northern Norway (UNN) at Tromsø; and McMaster University (MU), Hamilton, ON, Canada. During the early years of cooperation, Dr. Chashchin was the Director of the Scientific Laboratory of the North-West Public Health Centre Branch of the NWPHRC located in the town of Kirovks in the Murmansk Region. The primary focus of this long-standing collaboration was to assess and address issues that are important for maintaining the health of the population living in the border areas of Russia and Norway and included the reduction of occupational health risks among workers employed in mining, metallurgical and machine-building enterprises located in the north-western region of Norway and the adjoining Kola Peninsula in Russia. These industrial activities constituted essential components of the local industries. The ongoing Russian–Norwegian cooperation in the field of occupational medicine is an excellent example of the effective combination of intellectual potential and research technologies of multiple countries. It has resulted in the development of a scientifically based set of measures for practical implementation, contributing to the improvement of working conditions and preservation of the health of workers employed at enterprises where the joint research was carried out.

Quantitative analysis for detection of toxic elements in various irrigants, their combination (precipitate), and para-chloroaniline: An inductively coupled plasma mass spectrometry study

INTRODUCTION

Chlorhexidine (CHX) interacts with sodium hypochlorite (NaOCl) and herbal irrigants such as neem and tulsi to form precipitate which contains para-chloroaniline (PCA). No studies till date have reported about metal elements present in this combination as well as in irrigants.

AIM

The aim of this study was to evaluate the precipitate formed on combination of different irrigants, weigh the amount of precipitate formed, and to analyze 35 different metal elements in each irrigant, precipitate formed as well as in PCA.

MATERIALS AND METHODS

Seven irrigants, namely 2% CHX gluconate, 3% NaOCl, 17% ethylenediaminetetraacetic acid (EDTA), 5% neem, 5% tulsi, 5% Aloe vera, and 5% garlic were taken in different test tubes. Group (1-6): 1 ml of CHX is mixed with 1 ml of 3% NaOCl/17% EDTA/5% neem/5% tulsi/5% A. vera/5% garlic. Group (7-11): 1 ml of 3% NaOCl is mixed with 1 ml of 17% EDTA/5% neem/5% tulsi/5% A. vera/5% garlic. Group (12-15): 1 ml of 17% EDTA is mixed with 1 ml of 5% neem/5% tulsi/5% A. vera/5% garlic. Group (16-18): 1 ml of 5% neem is mixed with 1 ml of 5% tulsi/5% A. vera/5% garlic. Group (19 and 20): 1 ml of 5% tulsi is mixed with 5% A. vera/5% garlic. Group 21 includes 1 ml of 5% A. vera and 5% garlic. Each group is observed for any precipitate formation, and precipitate formed was weighed. Samples such as 2% CHX gluconate, 3% NaOCl, 17% EDTA, 5% neem, 5% tulsi, 5% A. vera, PCA, and precipitate formed in each group were analyzed for 35 different metal elements using inductively coupled plasma mass spectrometry (ICP-MS).

STATISTICAL ANALYSIS

One-way ANOVA and Post hoc Tukey's test for the precipitate formed.

RESULTS

Precipitate formation was seen in CHX + NaOCl (reddish-brown), CHX + EDTA (white), CHX + neem (light green), CHX + A. vera (green), CHX + tulsi (dark green), CHX + garlic (beige). ICP-MS analysis showed the presence of International Agency for Research on Cancer Group 1 carcinogens in NaOCl, CHX, EDTA, and PCA.

CONCLUSION

Carcinogenic metals are undetected in herbal irrigants which is found to be risk free alternatives in near future.

Binding of metals in dacryoliths by means of biomineralization

Dacryoliths are organomineral aggregates released from human lacrimal ducts, and are known to include a 1 to 3 % (by volume) of a mineral (inorganic) component This study was based on a collection of approximately 800 dacryoliths collected from a patient in Siberia. The shapes and sizes of mineral grains, their composition and their distribution in the organic matrix are very diverse; our detailed investigation identifies a number of inorganic phases that were not previously recognized. These were imaged on a scanning electron microscope (Tescan VEGA II LMU), and the chemical composition of the inorganic component was determined by energy dispersive X-Ray spectroscopy (INCA Energy350, Oxford Instrument), and X-ray analysis (X-ray diffractometer XPert PRO (PANalytical). For the first time, we identified the following minerals which can be divided into three groups: 1) oxide Si, pyrite, calcium oxalate, barite, which are often present in the tissues of the living organism and are also known in geological processes; 2) abundant complex mineral phases, consisting of Al, Si, K and Ti or Fe (titanium and iron aluminosilicates), which are also present in organism but have no analogues in the abiogenic environment; and 3) oxygen-containing compounds of Ni and Pb-Cr (possibly nickel oxide and lead chromate, respectively) which are only found in the abiogenic environment. Those mineral phases of biogenic origin are due to an endogenous (pathological) process in the body caused by internal factors (hypoergosis and metabolic disorders). This biomineralization may have a role in the removal of toxic and / or excess ions of Fe, Ti, Cr, Pb, Ni, Al, and Si from tissues.

An Overview of Carcinogenic Heavy Metal: Molecular Toxicity Mechanism and Prevention

Almost all heavy metals are serious toxicants as carcinogens. However, due to their chemical and physiological properties, heavy metals are useful in industrial areas including alloy, smelting and production of commercial products. Such applications increase the opportunity for heavy metal exposure. Waste from industrial processes is also a major source of environmental contamination and accumulation in the human body. Arsenic, cadmium, chromium, and nickel are classified as group 1 carcinogens by the International Agency for Research on Cancer, and are utilized commercially. In this review, we used molecular pathway analysis to understand the toxicity and carcinogenic mechanisms of these metals. Our analyzed data showed that above-mentioned metallic substances induce oxidative stress, DNA damage, and cell death processes, resulting in increase the risk of cancer and cancer-related diseases. Thus, we might think phytochelatin molecules and antioxidative phytochemical substances are helpful for prevention of heavy metal-induced cancer.