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Background Heterotopic Ossification (HO) is a common condition referring to ectopic bone formation in soft tissues. It has two major etiologies, acquired (more common) and genetic. The acquired form is closely related to tissue trauma. The exact pathogenesis of this disease remains unclear; however, there is ongoing research in prophylactic and therapeutic treatments that is promising. Conclusions Due to HO potential to cause disability, it is so important to differentiate it from other causes in order to establish the best possible management.

Risk through exposure to non-exhaust traffic emissions continues to increase as both the number of vehicles and traveling distances continue to increase with global urbanization. To better understand their impacts on the urban environment, a contaminant pathway was developed to describe important release mechanisms, transitory environmental media, and exposure media. Sources of contaminants were identified and characterized using published literature values. Concentrations of non-exhaust sources were used in conjunction with mean emission factors to estimate contaminant loads from individual vehicles (μg/km/veh). Published daily vehicle distances traveled were used to estimate total annual emissions (kg/yr) for the United States and Houston metropolitan area. This equates to approximately 5.1 million kg of Cu, 12.8 million kg of Zn, 4.9 million kg of Pb, and 2400 kg of Cd being released each year in the United States. Tires are responsible for 92% of total Zn emissions, with heavy-duty vehicles responsible for 77% of these emissions. Tires are also responsible for 86% of total Cd emissions. Brake dust contributes to 99.9% of Cu emissions. Wheel weights contribute approximately 94% of total Pb emissions. Identified best management practices include: 1. installation of grass buffer zones (e.g., rain gardens, vegetated swales) immediately adjacent to road surfaces, and 2. permeable pavements and green roofs near major highways. There are several limitations, assumptions and uncertainties associated with the study due to its static nature. However, evidence is substantial for the need to create new policies that address the pollution created by non-exhaust traffic emissions.

The elemental analysis of road dust can be used to determine the contribution of traffic-related metal emissions to the local environment. Previous studies have shown that brake wear, tire wear, and lead wheel weights release significant amounts of metals that lead to decreased biodiversity and degradation of urban streams. Highway pavement has not previously been considered as a source of metal inputs into the environment. To determine the extent that highway pavement contributes to metal loads in the local environment, road dust and pavement samples were collected for both asphalt and concrete pavement types on State Highway 59 in Houston, TX, USA. Samples were analyzed by ICP-MS to quantitate 9 metals: aluminum (Al), iron (Fe), vanadium (V), chromium (Cr), nickel (Ni), cobalt (Co), copper (Cu), zinc (Zn), and lead (Pb). A chemical mass balance receptor model that is commonly used for source apportionment of air pollution was applied to heavy metals in road dust, with brake dust, tire wear, wheel weights, and pavement materials as the emission sources. Pavement is shown to be the primary source of V, Cr, Ni, and Co in road dust, regardless of asphalt or concrete pavement type. Lead concentration in road dust is influenced by pavement type, with concrete pavement contributing approximately 45% of total lead in concrete road dust, while asphalt pavement only contributes 27% of total lead in asphalt road dust. Fly ash is the likely component of concrete pavement responsible for the higher contribution of Pb. An enrichment factor analysis indicates that Cr, Co, and V have low levels of enrichment compared to Cu, Zn, Pb, and Ni, indicating that pavement wear is generally a minor source of environmental metal contamination compared to brake and tire wear. Currently, brake and tire wear are the non-exhaust vehicle emissions of greatest concern; however, alternatives to fly ash should be considered to further reduce Pb and Ni concentrations in the environment.

Urban road dust is highly enriched with organic pollutants such as polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons, and herbicides that are released primarily from vehicles ...

Urban road dust can be highly enriched with trace metals such as copper, lead, zinc, and platinum group elements (PGEs) that are released primarily from vehicles. Concentrations of these metals are up to about 100 times higher than background levels. Lead concentrations in sediment core have declined dramatically due to phase out of leaded gasoline. Recent ban on the use of lead wheel balancing weight in Europe and in some US states will accelerate the decline of lead in the environment. Concentrations of copper, zinc, and PGEs in sediments in many urban areas have increased continuously due to increase of urban sprawl and increased numbers and travel distance of vehicle. Wear of brake pads and tyres are the primary sources of copper and zinc in urban road dust. PGEs have been released from catalytic converters since the mid-1970s. Contaminated urban road dust is picked up by stormwater runoff and delivered into local receiving waterbodies (e.g. streams, rivers, lakes, and estuaries). Concentratio...