Slag from nickel smelting operations in the Sudbury basin in Ontario, Canada, has become ubiquitous. This material rich in heavy metals such as iron, upon ingestion has the potential to effect physical, radiological, chemical, mechanical, and structural changes in biological systems. In this work, we analyzed the effects of slag ingestion through diet, on several quantitative and qualitative parameters of the tibio-tarsal bones in pigeons (Columbia Livia Domestica). The specimens were maintained on a seed diet and divided into a control group (n = 9) provided (normal) clean limestone grit, and an experimental group (n = 9) provided slag-based grit, both for a period of one year. Their tibio-tarsal bones were harvested for analysis. Quantitative analytical methods included conventional density measurements, caliper-based cortical thickness measurements, bone mineral density measurements using Dual Energy X-ray Absorptiometry (DEXA), calcium and iron concentration measurements using mass spectrometry, and the determination of Young's Moduli and ultimate breaking strength (both in compression) using a universal testing machine (UTM). Qualitative microscopy studies, both optical and electron -including energy dispersive spectroscopy (EDS) -were carried out for both sample groups. A Welch's t-test (single tail) was used to compare means of the seven quantitative parameters between control and experimental samples; in six of these parameters, a statistically significant difference was found (p ≤ 0.05). Microscopy, both optical and electron -coupled with EDS analysis -revealed structural differences in bone between the two groups. Engineering hardness testing of grit types in the dietary components revealed that the slag ingested by the experimental group was approximately twice as hard (Brinell and Rockwell hardness) as the limestone grit in the control group diet. We conclude that slag ingestion through diet in the species examined, is associated with measurable changes in mechanical, chemical, structural, and radiological properties of the tibio-tarsal bones.

The Sudbury Basin in Ontario, Canada, has been heavily mined for over 150 years due to the presence of sulphide ores rich in nickel and copper. Slag is a by-product...

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A new 125I source under the name Braquibac has been developed in Argentina for interstitial brachytherapy applications. The aim of this work is to study the new seed's design and to calculate its dosimetric parameters. Radiographic and destructive tests were carried out on inactive seeds to determine the physical characteristics of the source. Values of g(r), Lambda, F(r, Theta), and phi(an)(r), were obtained in water and air by simulation using the MCNP5 Monte Carlo code according to the methodology recommended in TG-43 and updated in TG-43U1. The dose rate constant was determined to be 0.937+/-0.004 cGy h(-1) U(-1) (overall statistical uncertainty +/-2.7%). Sk per unity activity was calculated to be 0.671+/-0.003 cGy cm2 h(-1) mCi(-1) by simulation of the seed in dry air using point detectors. Spectroscopic studies for both the new and the Amersham model 6711 seed were performed using an HPGe planar detector. The emission spectra of both seeds proved to be very similar. The anisotropy of the total photon intensity in air was measured in planes containing the seed's short and long axes using the HPGe detector. The minimum photon intensity for the new seed was 31.14+/-3.10% of the transverse intensity.

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