Life’s a… Son of a Beach!

Life’s a… Son of a Beach!

What’s that black stuff on my feet? Seep Oil? Natural? Whatever – what can it do to me?


SOS documented in our last blog how natural oil seeps can negatively impact the wild creatures who live in and around them.   What about the human creatures?

As we stated, the first thing we notice as beachgoers is the tar on our feet – but how does that tar get from the seeps to our feet?

State and federal agencies, as well as UCSB researchers, study this phenomenon on a regular basis.  Photos from the U.S. Geological Survey (USGS 2013) and the California Department of Conservation can help connect the dots (or tar-balls!).

Take this one, for instance

“This natural oil seep, at the base of a sea cliff near Santa Barbara, covers the beach sand with an impressive build-up of black asphaltum. This tar-like substance is eroded by waves to form pesky tar-balls, which are carried by longshore currents to other beaches, miles away.”

Our studies support the hypothesis that natural oil seepage from sea floor vents are responsible for the majority of tar-ball accumulation on Southern California beaches. Oil fingerprinting provides the crucial tool to verify of the origin of this deposited oil (USGS 2013).

Natural crude-oil seeps are common in regions of petroleum-bearing formations. This natural contamination may result in human exposures to crude oil and subsequent associated health risks. Risks from natural contamination sources are often referred to as background risks (Sullivan 2011).

However, researchers on human health impacts use different terminology to refer to risks from spilled oil.  Health risks associated with exposures resulting from accidental releases of chemicals into the environment are referred to as additional or incremental risks (Sullivan 2011). Why should there be a difference in terminology if the oil itself is the same crude?

Crude oil is composed of thousands of hydrocarbons and the composition begins to change, or “weather”, as soon as it enters the environment. Contaminants of concern in crude oil are the volatile organic compounds (VOCs), especially the aromatic hydrocarbons, BTEX (benzene, toluene, ethylbenzene and xylene). The other major compounds of concern are the polycyclic aromatic hydrocarbons (PAHs) (White 2011).

The negative health effects of PAHs are well established for modern human populations but only recently have these impacts been studied in prehistoric contexts.


As an example, take the early Chumash tribes, who used tar from local seeps to waterproof the canoes they used to travel from the mainland to nearby ocean islands.  PAHs are the main component of fossil bitumen, a naturally occurring material used by past societies such as the Chumash Indians in California as an adhesive, as a waterproofing agent, and for medicinal purposes. Coastal Chumash Indians were increasingly exposed to these PAHs as cultural uses of bitumen and consumption of PAH-contaminated water and marine foods intensified over time. A skeletal analysis revealed a decrease in cranial size in both male and female adults on the northern Channel Islands across a time period of roughly 7,500 years, consistent with a previously suggested decrease in population stature. These trends may be related to increased bituminous PAH exposure, as earlier research has shown that human PAH uptake can compromise fetal growth and development.


We certainly share the tar-ball experience with those past inhabitants of our coast.A recent Edhat posting by Paul Costales was entitled “Tar: A Local Beach Tradition” and highlighted what surfers go through when trying to find that perfect wave. While writing about the lack of waves, he added that “… as the flat days add up to weeks, our natural tar seeps compound our frustration too. As if having a flat surf session isn’t bad enough, you also have to get covered in tar and spend a lot of time getting it off. Other ocean-goers are taking some big hits too. Just last Friday a friend was swimming at Goleta Beach and was covered in more tar then he’s ever been covered in from oceangoing along our local coast. Goleta Beach isn’t typically considered one of the really tarry beaches around here either. The tarriest beaches, not surprisingly, have some tarry names, Tar Pits and Coal Oil Point (Sands and Deveraux) being the most popular tar prone surf beaches in these parts.”


So tar-balls on the beach are definitely a conversation topic for surfers. Do they also encounter oil in the water while surfing?

UCSB Surf Oil As a UCSB Sophomore, Joey Krueger was interviewed for an article in the Santa Barbara News-Press (Allison 2008). The mechanical engineering student and surfer was quoted as saying “It’s pretty bad out here. When I go out surfing for 1 hour I can literally feel the tar and oil in the back of my throat. I actually get a sore throat if I’ve been surfing too long.”

While we don’t ingest oil while we’re in the water, at least not in the quantities that marine mammals and birds do, it can get on our skin – and people who spend time in the water definitely start to feel similar impacts to those creatures.

We also inhale the fumes. c The natural gas and oil seeps beneath the Santa Barbara Channel cause gas to escape from the ocean floor and float to the surface like carbonated soda bubbles, releasing methane, a potent greenhouse gas, into the atmosphere.

Santa Barbara County’s air quality has historically violated both state and federal ozone standards. According to the county’s 2007 Clean Air Plan, offshore natural gas and oil seeps is a major source of the county’s air pollution and responsible for putting more than 22 tons of reactive organic gases into Santa Barbara’s air every day. By comparison, all of the motor vehicle trips in Santa Barbara County produce 18 tons of hydrocarbons each day.  However the 2010 update of the Clean Air Plan evaluates only human-generated sources of air pollution. Is the evaluation of air quality complete without acknowledging the emissions from natural seeps?

Mr. Costales also wrote about the impact of Venoco’s activities near Coal Oil Point.

“It is said that our local offshore drilling has reduced pressure on the oil and gas fields allowing the natural seeps to slow down. Local oil operator Venoco, has several “tents” they keep out over some of the offshore seeps. They collect oil and gas bubbling up from the ocean floor and pipe it to their onshore facility. It seems oil companies get a bad rap from a lot of folks, but in this Venoco should be thanked for collecting all of that junk that is going to end up on our beaches and turning it into something we heat our homes with.” 

Why should we continue to be impacted by the oil seeps when there is a Sole-ution?



    1. Allison, B. 2008. What About Our Oil?  Santa Barbara News-Press. August 28, 2008.


    1. Sullivan, M. 1991. Evaluation of Environmental and Human Health Risk from Crude-Oil Contamination.  Journal of Petroleum Technology, Volume 43. Number 1. Society of Petroleum Engineers.


    1. 1 Department of Anthropology, University of California, Santa Barbara, California, USA, 2 Division of Biophysics, Stockholm University, Stockholm, Sweden, 3 Museum of Natural and Cultural History, University of Oregon, Eugene, Oregon, USA, 4 Department of Analytical Chemistry, Stockholm University, Stockholm, Sweden


    1. USGS 2011.  Fate, Volume and Chemistry of Natural Seeps in the Santa Barbara Channel/Southern Santa Maria Basin” Final Technical Summary, USGS SIR 2011-5210, BOEM OCS STUDY 2011-016


    1. Costales, P. 2013. Tar: A Local Beach Tradition


    1. SBAPCD 2011. 2010 Clean Air Plan. Santa Barbara County Air Pollution Control District, with Santa Barbara County Association of Governments (SBCAG). January 2011.


    1. USGS 2013. Natural Oil & Gas Seeps in California – The Effects of Seeps on the Environment. U.S. Geological Survey (Pacific Coastal Marine Science Center)  and the California Department of Conservation.


      USGS SIR 2011-5210, BOEM OCS STUDY 2011-016


    1. Could the Health Decline of Prehistoric California Indians be Related to
      Exposure to Polycyclic Aromatic Hydrocarbons (PAHs) from Natural Bitumen?


  1. White, L. 2011.  Deepwater Horizon Study Group Working Paper – January 2011, Human Health.




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