The sound of a marching band is influenced by the OH-PAH-PAHs of big brass tubas. However, OH-PAH-PAHs have now become the buzz word for pollutants that influence the Sound of Long Island.
OH-PAH-PAHs represent the persistent class of toxic chemicals that coat our highways and, through storm water runoff, wash into our Harbors. Due to the daily volume of traffic over Interstate-95’s Yankee Doodle Bridge, this stretch of roadway represents the major contributor of these contaminants in Norwalk Harbor. Hydroxylated polycyclic aromatic hydrocarbons (OH PAHs) and polycyclic aromatic hydrocarbons (PAHs) are pollutants generated mainly from vehicle emissions, smoke and soot from combustion engines, and material left behind by vehicle tires. OH-PAH-PAHs bind readily to dust and dirt particles that get picked up by rainwater as it pours across the stretch of I-95 between Exits 14 and 16. The rainwater mixture over this impervious surface flows either from storm drains or directly into Norwalk Harbor.
OH-PAH-PAHs are major concerns in the environment and cause health issues which we need to understand. The impact of these toxins extends to plants, marine organisms, birds, and animals. Of considerable importance is the ability of OH-PAH-PAHs to rapidly degrade within the aquatic environment. Usually, “degradation” refers to a decomposition of these chemicals to less toxic substances. However, the Environment Protection Agency has shown that the degradation of OHPAH-PAHs by ultraviolet (UV) radiation from the sun greatly enhances their toxicity. The mortality of marine organisms from OH-PAH-PAHs is strongly related to the extent of UV-A (320-400 nm) exposure.
Shellfish are at particular risk for the phototoxic effects of these contaminants because of their accumulation within the sediment. Once OH PAH-PAHs are incorporated into sediments they are somewhat immobile because of their highly fat-soluble nature that limits them from dissolving completely in water. High temperatures coupled with solar radiation accelerate OH-PAH-PAHs photodegradation which explains the seasonal cycle of their toxicity particular during summer months. Juvenile clams (.5-2 mm) when exposed when exposed to UV-treated OH-PAH-PAHs for 96 hours either lose their ability to rebury in control sediment or exhibit a reduced capacity to do so.
Short-term health effects of OH-PAH-PAHs on humans depend mainly on the length and route of exposure and the amount to which one is exposed. Occupational exposures to high levels of OH-PAH-PAHs have resulted in symptoms such as eye irritation, nausea, vomiting, diarrhea and confusion. Mixtures of OH-PAH-PAHs on skin cause marked irritation and inflammation. Long-term health effects of OH-PAH-PAHs are more problematic and include decreased immune function, cataracts, kidney and liver damage, and lung abnormalities (asthma-like symptoms). Chronic exposures to these hydrocarbons can also cause fetal mutations, developmental malformations, and tumors. Of particular concern regarding cancers is that solar modifications of OH-PAH-PAHs cause them to have steroid hormone (estrogenic)-like properties and thus can influence hormone-sensitive pathways in urinary bladder, colon, breast and prostate tissue.
UV radiation also enhances toxicity of OH PAH-PAHs to algal species by greatly decreasing their growth. The irony of these effects on algal blooms and the trend toward less turbid water and greater penetration of UV light to river and lake bottoms is that this can lead to greater phototoxicity from sedimentbound OH-PAH-PAHs.
In closing, with rehabilitation of the Yankee Doodle Bridge currently underway, we have an excellent opportunity to eliminate these pollutions from Norwalk Harbor. The Norwalk Harbor Management Commission looks forward to measures that the Department of Transportation (DOT) will take to prevent stormwater discharge directly into the Norwalk River and to minimize OH-PAH-PAH contamination of Norwalk Harbor. Guidance and the authority vested in the Department of Energy and Environmental Protection (DEEP) will be required to assist in these matters. Most importantly, our state legislators need to assure that the DOT complies with best management practices to control pollution into Long Island Sound. Use of stormwater control systems over the Yankee Doodle Bridge would not only benefit Norwalk Harbor, but would be applicable to other highway bridges crossing Connecticut’s coastal waterways.