Commercialshipping contributes to Houston poor air quality
by Erika McDonald
A report released recently by Washington DC-based Environmental Defense attributes roughly one million tons of health-threatening pollution to America's commercial shipping industry. A scientist in the group's Austin office, Ramon Alvarez, said the two pollutants of greatest concern were nitrogen oxide, a key ingredient in ozone formation, and particulate matter, because of the associated health risks. Ozone is known to cause respiratory illness and skin irritation. Particulate matter also impairs lung function and is a major cause of heart of disease.
Alvarez advocates mandatory emissions reductions on commercial ships in the interest of public health.
"The fact is these emissions are contributing to significant public health effects in the US and abroad," Alvarez said, "and controlling the emissions would yield significant public health benefits."
Houston is home to one of the largest ports in the nation. In this region alone, commercial shipping accounts for the same amount of pollution created by 280,000 trucks and SUVs. While environmental agencies have developed plans to reduce emissions from land vehicles, marine vessel emissions have gone largely unregulated.
The Texas Commission on Environmental Quality estimates that by 2007, pollution from commercial shipping in Houston will surpass pollution levels related to construction across the state. Alvarez said that while the state legislature deemed construction-related pollution such a significant contributor to the state's poor air quality as to allocate more than $100 million to construction emissions, it has left marine vessels virtually unregulated.
"If emissions from ships are comparable to emissions from construction, it only seems logical that we should be devoting a similar level of effort to reducing emissions from the ships," he said.
The state also directed a significant portion of Texas emissions reduction plan funding toward commercial diesel engines. Alvarez said most ships run on Bunker fuel, which is dirtier and heavier than diesel.
Regulators may find it difficult to address commercial shipping pollution because much of the activity that impacts local health takes place in international waters outside federal jurisdiction. But Alvarez insisted there is much state and federal regulators and legislators can do to monitor vessels such as tugboats and ferries that operate only in local waters. For example, Environmental Defense recommends that state lawmakers pass measures to ensure the funds currently earmarked for road vehicle emissions reductions are made available to reductions for ship engines. At the national level, Alvarez said the Environmental Protection Agency could require the same emissions standards imposed on other commercial vehicles.
Environmental Defense also recommends that federal lawmakers join international treaties such as MARPOL Annex IV recently ratified by 15 nations to restrict emissions for commercial ships. The report, “Smog Alert: How Commercial Shipping is Polluting Our Air” is available online at www.environmentaldefense.org/go/cmv .
