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Natural Perspectives: Coming to a beach near you

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Technology constantly changes, often making our world safer, and making work simpler, faster, and easier. A new molecular technology is due to arrive in our area soon that will do all of that for us in terms of beach pollution.

Last weekend, Vic and I attended a Southern California Academy of Sciences symposium at Occidental College in Eagle Rock. There, we learned about an innovative method for monitoring bacterial pollution at ocean beaches.

The keynote speaker, Stephen B. Weisberg, PhD, talked about a new molecular method for real-time monitoring of beach pollution. Weisberg is executive director of the Southern California Coastal Water Research Project in Costa Mesa. Yes, there is a state-of-the-art water research laboratory in Costa Mesa.

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“Computers have transformed our ability to do analytic work,” Weisberg said. “Genomics is this generation’s equivalent.”

Genomics is the study of the genome, which is an organism’s genes (DNA). And as anyone who watches CSI on television knows, DNA analysis has revolutionized how things are done by police forensics departments. Homeland Security, the military, and various medical fields use it as well. All individuals (except identical twins or clones) have a unique set of genes. And all organisms can be identified as to species by their DNA fingerprint.

Weisberg and co-workers have developed technology for using remote automated DNA analysis to monitor bacteria at ocean beaches. Weisberg showed a picture of a “Beach Closed” sign such as is put up now to warn people of beach bacterial contamination. Those warnings, however, are based upon monitoring that was done the day before. The contamination issue may be irrelevant by the time a sign goes up.

“The sign should say, ‘Water was bad yesterday, don’t know about today, come back tomorrow,’” Weisberg said.

That’s because the way that beach monitoring is done today requires laboratory culture of ocean water samples to see what levels of bacteria might be present.

A technician travels to various beaches to collect samples early in the morning. The samples are brought back to the lab and grown on agar plates, typically overnight.

By the time results can be read, it is the next day. If there had been contamination, the beaches aren’t closed until the next day. But by then the problem well could be over. So all that today’s technology tells us is that we shouldn’t have been swimming there the day before!

Things are about to change. New automated remote technology exists that will give results within two hours, not a day, and can even identify the different bacterial species that are present. Additionally, this new DNA technology is not prone to the false positives that are typical of culture techniques.

DNA analytic technology has taken the same enormous strides that calculating ability took in the past. When Vic was working in the lab during his postdoctoral fellowship, DNA sequencing was done by hand, slowly and laboriously. Today it is all automated.

A new technique called QPCR can produce results in 90 minutes. QPCR stands for Quantitative real-time Polymerase Chain Reaction. It could also stand for quick PCR, because it is so fast.

It will allow health agencies to determine within two hours whether or not a beach should be closed to shellfishing or swimming. The results will tell not only the level of bacterial contamination, but also what species of bacteria are present. The EPA is expected in November to approve use of this technique, but will not require it.

Currently, the machinery for performing this technique is fitted into a large metal drum that is attached to a pier. The results are remotely sent back to the laboratory. A person who is monitoring the results can phone the lifeguards, who can close the beach within two hours of when the contamination was detected.

In the future, there may be moored pumping stations and real-time telemetry to shore that will allow monitoring of harmful algal blooms, also known as red tides. Scientists are working on developing a reference library of DNA sequences for different species that might be encountered during a harmful algal bloom. Think of this technique as a form of genetic bar coding.

Many challenges remain before this technology is widely available. For example, organisms that were supposedly in different taxonomic groups based on morphology have been shown by DNA technology to be nearly identical.

They are finding that up to 10% of the species that they are examining by DNA technology aren’t really separate species but are merely different forms of the same species. That is analogous to thinking that Dalmatians and Chihuahuas are different species based on how they look. Molecular biologists and taxonomists are going to need to work together to figure this out.

Some of the other challenges that remain include standardization of methods, development of quality assurance parameters, and commercialization of reagents and equipment.

Weisberg

mentioned that a prototype QPCR machine is in use at the Santa Monica Pier. This device continuously monitors the water, sending results back to shore by telemetry.

The really exciting news is that a second machine will soon be placed in southern California, either at Newport Pier or Huntington Beach Pier. The future is coming to a beach near you within the next few months.

VIC LEIPZIG and LOU MURRAY are Huntington Beach residents and environmentalists.

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