Probing for pollution at Mission 31

When North­eastern assis­tant pro­fessor Loretta Fer­nandez was a kid, she “wanted to be Jacques Cousteau” (her words, her emphasis). She wanted to live on The Calypso, the boat from which the leg­endary ocean explorer would set out on his epic under­water journeys.

So when the oppor­tu­nity to take her research to Mis­sion 31–the month­long exper­i­ment in under­water living lead by Cousteau’s grandson, Fabien Cousteau–Fernandez didn’t bat an eyelash.

As I wrote in a news@Northeastern story recently, Fer­nandez uses these crazy-​​simple con­trap­tions to col­lect crazy-​​important data about marine pol­lu­tion. And despite their sim­plicity, these contraptions–which con­sist of a piece of metal cov­ered by a strip of plastic–she does some heavy duty math to extract the sto­ries they have to tell about the ocean.

Here’s how it works, in case you don’t want to go read the other story right away: Organic pol­lu­tants are typ­i­cally large, hydrophobic mol­e­cules and so are the fatty tis­sues of living organ­isms. Since like-​​tends-​​to-​​dissolve-​​like, those pol­lu­tants tend to end up in the organ­isms that hang out in the water. You know, the fish.…that we eat. So, yes, those pol­lu­tants even­tu­ally end up in us, too.

The mol­e­cules in Fernandez’ plastic strips are also large and hydrophobic, so pol­lu­tants col­lect inside them at about the same rate as they do in fish.

The pas­sive sam­plers Loretta Fer­nandez uses con­sist of a wire frame cov­ered in a thin sheet of plastic. Photo by Mariah Tauger.

For Mis­sion 31, which just wrapped up today, Fer­nandez sent down two sep­a­rate exper­i­ments. The first was a time series analysis which will allow her to con­firm the math­e­matics that she’s been relying on for this par­tic­ular type of plastic.

There have been a lot of inde­pen­dent cal­cu­la­tions to add con­fi­dence to the num­bers, but no one has done a good exper­i­mental analysis to con­firm them yet.  “Usually we don’t do these types of exper­i­ments,” Fer­nandez said, “because to send divers down four times in a month is expen­sive and hard.” But the Mis­sion 31 team was already down there and it wasn’t much skin off their backs to set up the exper­i­ments for her.

(This might be a good time to men­tion that Fer­nandez doesn’t dive. She never was able to achieve that child­hood dream of becoming Jacques Cousteau…or even a diver…because, well, she gets motion sick­ness and is afraid of the water. She still goes out on the boats though, but that means “scopo­lamine patches every­where and I still end up, you know, heaving over the side in between set­ting sam­plers up.” Just another reason why Mis­sion 31 was so useful for her!)

The second exper­i­ment is per­haps a little more exciting from a layperson’s per­spec­tive. In this one, she had the “aqua­nauts” (the sci­en­tists living under the sea for Cousteau’s 31-​​day mis­sion) set up sam­plers at three dif­ferent depths on the reef. This pro­vides a lot of “sam­pler mass” in which to col­lect organic contaminants.

We’ll just see what sort of organic con­t­a­m­i­nants we see in this oth­er­wise pris­tine envi­ron­ment,” Fer­nandez said. She expects that some of the things she sees will be residual oil com­pounds from the Gulf oil spill and the dis­per­sants that were used to break up that oil. While the Conch Reef where the exper­i­ments were car­ried out isn’t in the gulf per se, it does get an influx of Gulf waters so it’s highly prob­able that Gulf con­t­a­m­i­nants will end up here as well.

Fer­nandez’ sam­plers are decid­edly easy to set up and once in place require very little over­sight. As she said, “they really are pas­sive sam­plers.” This video is proof: