Analytical Approaches for Organic Compound Properties

The report of Leistra on reported versus estimated boiling points and vapor pressures for pesticides provides an interesting case study in mathematical underpinnings for the phenomena investigated. Reports of chemical properties are available from many online databases such as ChemSpider, PubChem, and others. But these aggregate other sources of data to get chemical properties. In some cases, they are from a manufacturer. Of course, manufacturers often report values without a method or explanation of how it was determined. The article makes a number of assumptions, the most important of which is that reported values are based on experimental observations. That’s

The Implementation of the Clean Water Act

The federal Clean Water Act is a collection of laws passed by Congress that together form the principal federal law on preventing water pollution. This includes permanent lakes, rivers, streams, ponds, and other nonintermittent bodies of water. Passed in 1972, over the veto of President Nixon, the act was later amended in 1977 and 1987, and is administered by the Environmental Protection Agency, who has rulemaking and enforcement powers under the Clean Water Act. The Act addresses surface water contamination, focusing on wastewater treatment and pollution sources affecting navigable waters of the United States. The Act encourages the EPA to

Some Hurricane Science

Hurricanes are the topic of choice this year given Harvey’s record breaking destruction of the Texas coast and the unusual position of three concurrent North Atlantic hurricanes tracking as I write this. Given the circumstances, some are left wondering why this year is unusual. Not since 2005 have see so many powerful hurricanes. And even 2005, those were weaker compared to this year and less frequent. Some of us point to the dangers of climate change, though that is apparently up for debate. In order to understand the role of climate change, it helps to understand a bit of the

Irma is Not Category 6, but Could be

As Hurricane Irma continues to gain strength, some have started calling it a category 6 hurricane. The problem with this is the scale only goes up to 5. There are 5 hurricane strength categories and two sub-hurricane strength levels. We can see those plotted below. It is worth asking, if there were a category 6, 7 or even 8, what would that intensity be? What the demarcation point? The plot shows the scale is not strictly linear. There’s a smallish curve that tightens the bands at the top of the scale. In contrast, the Richter scale works the other way,

Maryland Watershed Stewards

I was recently appointed to the Howard County Watershed Stewards Academy‘s Advisory Committee and yesterday was my first meeting. I wanted to take a minute and discuss this program and the value it adds to the community. As I have talked about before, most of Maryland’s land drains into the Chesapeake Bay. Accordingly, it is important that our streams and waterways that drain into the bay are clean and healthy. If not, it can lead to fish kills and eutrophication. And that’s if we don’t just turn the Bay into hazardous waste. The Watershed Stewards are volunteers who help protect

Making the Things You Buy Better

For reasons too complicated to get into, I am taking a course in environmental chemistry. And that means I will be writing about it occasionally here. Because that’s the kind of thing I do. Acrylamide (ACR) is a common hydrocarbon used in industrial settings and found in some foods fried at high temperatures as well as some fruits. Industrially, ACR is used to manufacture some plastics and is also used in the wastewater treatment process. ACR is also a known neurotoxicant causing peripheral neuropathy. The exact mechanism of ACR on neurological systems is unknown, but some have suggested that ACR