KINSHIP: HAND IN HAND WITH CHIMPS IN UGANDA

         Little Rambo, four and a half years old, makes his selection.  After checking each of the six of us out, he reaches his long, hairy, black arms up towards Molly, and she obligingly scoops him into her arms.  Rambo casually slings his arms around Molly’s neck, and she walks through the forest with this orphaned chimpanzee, as if he were just another of her babysitting charges.  My 18 year old daughter, Molly, four people from the Netherlands and I are on a Forest Walk with ten young chimps living on 100 acre Ngamba Island in Lake Victoria, Uganda.  The island is a sanctuary for rescued chimps and represents a collaboration between the Chimpanzee Sanctuary and Wildlife Conservation Trust (CSWCT) and Wild Frontiers which handles accommodations and meals for overnight visitors.

             Most of Ngamba Island is an undisturbed tropical forest in which the 44 resident chimps wander all day, feeding, sleeping, grooming, playing and exploring.  Their internal clocks alert them to the times each day when their keepers bring silver buckets filled with a delicious variety of fruits and vegetables to toss over the high fence from raised observation decks.  Five to 10 minutes before each feeding session chimps emerge from the dense forest and settle on the grass by the electric fence which separates the chimps’ 95 acres from the 5 acres used by staff and visitors.  Some groom one another, while others stare into space or play quietly.  The silence is broken at the sight of approaching food bearers.  A crescendoing chorus of excited hoots fills the air and more chimps emerge single file from the forest.  Many of the chimps approach the dominant male of the group, look submissively into his face and call out, before heading for their meals.  The famous chimp ability to make tools is on display, when a piece of food falls onto the wrong side of the fence.  A chimp picks up a stick, breaks it to the appropriate size, pokes the stick through the fence, and pulls the errant food within safe reach.

            Day visitors to Ngamba Island can watch the 11 am and 2:30 pm feedings from the observation platforms.   It is a fascinating opportunity to watch chimp behavior up close in a natural setting.  The sanctuary manager gives a short lecture on chimps in Uganda, and visitors can buy handicrafts made by women on nearby islands, thereby building a positive relationship between the chimps and their neighbors. 

            Ngamba Island is one of 19 primate sanctuaries in Africa.  Such sanctuaries are essentially crisis centers, much like human refugee camps.  They house orphaned and confiscated primates who have become victims of conflict with humans.  Threats to chimps include the hunt for bush meat (chimps are eaten by people in central and west Africa), capture as pets, and killing in response to chimp raids on crops.  Rescued chimps cannot be released into the wild, both because there is no undeveloped habitat available, and because chimp territoriality, which is violently enforced, prevents placing them in areas already inhabited by chimps.  So as not to overpopulate the chimp space on Ngamba, the females are all on birth control.

            The ultimate treat is for those visitors who opt to stay overnight on Ngamba.  There are four luxurious two-person tents, each perched on a raised deck at the edge of Lake Victoria.  As I sit on our deck, the open expanse of the lake is hidden by huge bushes rising out of the water five meters offshore.  The shallow strip of lake in front of me is teeming with geese, ducks, ibises and egrets.  This cozy hideaway puts me in the midst of an avian paradise where 150 species of birds thrive.   Beside our tent, a pair of elegant spur-winged lapwings take turns sitting on eggs which lie in plain sight on the grass, dangerously exposed to marauding monitor lizards.  A short way up the path, which leads to the chimps’ side of the island, a worried water thick-knee trots around near its fuzzy, striped chicks, huddling camouflaged under a bush.  The bushes growing in the shallows are bedecked with weaver nests, and the busy, yellow birds flit from branch to branch, constantly patching up their hanging, tear-drop nests.  An African fish eagle soars over the island and perches in a tall tree, its brilliant white head and tail glowing in the evening light.  As the sky darkens, thousands of fruit bats fill the air above the island, all heading toward the mainland to feed for the night.

            Wild Frontiers serves up fantastic meals in the open-air dining hut.  Our four-course dinner features tilapia fingers, green bean soup, savory chicken, rice, sauteed vegetables and chocolate cake.  Afterwards, we sit around a bonfire under the full moon-lit Ugandan sky and listen to lapping waves, bird calls, and a few outbursts from the settling chimps.

            The next morning six of us gather for the Forest Walk with some of the younger chimps.  At 7 am we are privileged to pass through the gate into the chimps’ side of Ngamba.  A handful of chimps who evaded the call to return to their cages for the night (this is done, so that the health of each can be monitored and medicines dispensed), sit idly around, possibly regretting missing the breakfast just dispensed to the cooperative chimps.  In a minute, the ten chimps selected for our Forest Walk, amble down the chute between the cages and freedom.  Initially, they ignore us, wandering off to the edge of the forest.  We follow and sit patiently near them, and, then, Rambo selects Molly to carry him.  A smallish female taps my leg and indicates that she wants to hop onto my back.  Honored, I lean down and up she climbs.  I am stunned by her weight; she feels like an enormous boulder, her powerful muscles accounting for a bulk not obvious in looking at her. 

            Our precious hour with our chimp companions passes too quickly.  We head into the forest where the light drops dramatically and chimps melt away into the vegetation with a few steps.  We sit in a small clearing, and some chimps break off  leaves and thick plant stalks to eat.  A discarded stalk I taste reminds me of celery.  Humans and chimps pair up and groom one another.  Bili, rescued from the Democratic Republic of the Congo in 2001 when she was bald, parasite-laden and badly scarred, is my grooming partner.   I rest my head in her lap, and she gently scrapes her nail over my scalp and neck, occasionally pressing her lips to a particular spot. 

            Being with the chimps is simultaneously transcendent and utterly ordinary.  Our kinship is unmistakable.  The chimps touch us in a lackadaisical way.  We touch them with the casual familiarity we use when touching our own young children.  We all take turns tickling Rambo who laughs uproariously.  The chimps’ amber eyes reflect wisdom and depth. 

           

            Once again back on the human side of the fence, I feel stunned by the experience I’ve just had.  Since cameras are not allowed on the Forest Walk, all I am left with are my memories and the sweet, horsey smell lingering on my hands from touching the chimps.

Rescued chimpanzees on Ngamba Island, Uganda during one of four daily feedings.  Chimps and humans share 95% of their DNA, and this photo, as well as walking hand in hand with a chimp in the forest, vividly confirms our close relationship.

 

Rescued chimpanzees on Ngamba Island, Uganda during one of four daily feedings.  Chimps and humans share 95% of their DNA, and this photo, as well as walking hand in hand with a chimp in the forest, vividly confirms our close relationship.

           

A Ugandan saying, “One by one makes a bundle” explains why it is worthwhile to save each individual chimp who has been captured for the pet trade or for bush meat or whose mother was killed in retaliation for crop raiding.

Reaching Puberty Early

Ed note: This essay was published in the July/August 2008 print edition of ColorLines magazine. (http://www.colorlines.com/archives/2008/07/reaching_puberty_early.html)

JUST AFTER MY DAUGHTER TURNED 7, she came to me and nervously announced that she had bumps on her chest. I felt beneath her nipples, and, indeed, there were prominent, hard lumps. A friend had gone through this with her 7-year-old, so my first fleeting panic about cancer was replaced by the alarming realization that my little girl was developing breasts. I made an appointment with our family doctor, but it was two weeks off.

In the meantime, I googled “premature puberty” and discovered the literature on environmental causes of early puberty. I also found that family history, prenatal and early postnatal exposures were key. I had adopted my daughter when she was 3 months old. While I knew she’d never been breastfed, I knew little else about her history or that of her birthmother. I set out to find out everything I could about early puberty in girls, trolling through the medical literature, gleaning library shelves, exploring the websites of environmental organizations and conversing with scientists who are grappling with this issue.

Why was I so alarmed about my Black daughter starting puberty at the age of 7? As a white mom who first menstruated at 13, I was afraid of the prospect of my child dealing with sexuality at such a young age. My fear increased as I found studies showing a litany of social risks for girls who mature early: poor self-esteem, increased depression, early sexual intercourse and increased drug and alcohol use and abuse. Most worrisome to me were the increased health risks associated with early puberty: breast cancer, type II diabetes, cardiovascular disease and polycystic ovarian syndrome. Early-maturing girls reach their adult height early, and if this occurs by age 12, they have a significant risk of getting a very aggressive form of breast cancer. I knew that I had to take action.

One of the first discoveries I made was that girls were having different experiences with puberty based on race. A 1997 study, conducted at pediatricians’ offices nationwide, found that girls were showing the first signs of puberty about a year earlier than was considered normal. Most striking was that Black girls were beginning puberty about a year earlier than white girls. Compared with 8-year-old white girls, about four times as many Black 8-year-olds grow pubic hair and develop breast buds. The age when girls get their first periods has also dropped (though less dramatically) over the past 30 years, and Black girls precede white girls by half a year in this regard.

Dr. Paul Kaplowitz of the Children’s National Medical Center in Washington, D.C., has suggested that genetic differences between Black and white people may explain early puberty in Black girls. He wonders if the genes involved in insulin resistance, which occurs more often in Black people, may predispose Black girls to earlier puberty by affecting their hormone levels. However, in 1944, girls of both races started puberty at the same age. Today, girls from well-off Black families in South Africa and Cameroon get their first periods at least one year later than Black girls in the United States, and Kenyan Black girls menstruate four years later, on average, than Black girls here.

Doctors have suggested that the dramatic rise in childhood obesity has contributed to earlier puberty. We know that being fat increases the estrogen in a girl’s body, and estrogen is the chief trigger for breast budding. At every age, the percentage of Black girls who are overweight is significantly higher than that of white girls. However, researchers have concluded that, while obesity plays a role, it is not the only cause of early puberty. My daughter, for example, is very thin, so obesity wasn’t even a possible culprit in her case.

When I began looking into environmental causes, however, a clearer picture began forming. Dr. Sandra Steingraber, author of the Breast Cancer Fund’s comprehensive 2007 report “The Falling Age of Puberty in U.S. Girls” considers early puberty to be “an ecological disorder” resulting from a complex web of environmental influences. Pollutants, plastics and chemicals may be the hidden causes of early puberty in girls, and Black girls seem to be more vulnerable.

•••

When I discovered my daughter’s breast buds, I emptied my house of plastic water bottles and stopped letting her eat school lunches that are heated in plastic. I did this just on a hunch. With great relief, I watched her breast buds recede over the next month. In fact, by the time she saw the doctor two weeks later, her breast buds had shrunk to the point that he was unimpressed. A friend whose daughter sprouted pubic hair at the age of 6 and a half tossed out all of the plastic in her house and had the satisfaction of watching the pubic hair vanish.

These anecdotes are not backed by hard statistics, because studies in this area have yet to be prioritized, but they fit perfectly with what we’ve recently learned about plastics.

Polycarbonate plastics (imprinted with a number 7) are made hard and durable by bisphenol A, or BPA, one of the most abundant synthetic chemicals nowadays. More than six billion pounds of BPA are produced in the United States each year. It is in so many products that it is impossible to name them all, but they include dental sealants and fillings, some food containers, 80 percent of food can liners and many water bottles. BPA also leaches from landfills into groundwater and is found in indoor air. A 2008 report by the Centers for Disease Control showed that 93 percent of people randomly tested had BPA in their urine, but the highest levels were found in Blacks, women, young children and poor people.

Most baby bottles are made of polycarbonate plastic. It turns out that 3.5 ppb (parts per billion) of BPA leach into milk from new baby bottles and eight times that much from worn and heated bottles. Black babies are primarily bottle-fed—only 5 percent of Black women breastfeed exclusively for the first six months of their babies’ lives, as the World Health Organization recommends. Poor Black women, in particular, are discouraged from breastfeeding by the free formula dispensed by the Women Infants and Children (WIC) program.

Last year, the federal government sponsored a gathering of 38 medical researchers to determine what effects BPA has on humans. The group reported that BPA acts the same way in humans as it does in animals and the levels in humans are causing negative health effects. It’s possible that BPA might be contributing to our obesity epidemic, which is already tied to early puberty. Most relevant to us: the scientists concluded that early puberty is directly linked to low-dose exposure to BPA.
Another group of synthetic chemicals, used to make plastic flexible, has been linked to early breast budding in girls. These chemicals, called phthalates, are used to make polyvinyl chloride, or PVC, (identified by a number 3) which is what many water pipes are made of. They’re also found in food wrappings, the lining of cardboard boxes that hold liquid or fatty foods, medical tubing, time-release capsules, kids’ toys, insect repellents and countless personal care products. This last category includes shampoo, lotions and deodorants. The CDC found that phthalates compose up to 3 percent of some of these products. Women of childbearing age are the group most exposed to phthalates.

Another way we’re exposed to hormones, of course, is through our diet. There are six sex and growth hormones permitted by the Food and Drug Administration in commercial beef cattle. When people eat beef, they are adding these hormones to their systems. No one knows if eating commercially produced beef plays a role in early puberty, but suspicion is warranted.

•••

Black people suffer disproportionately compared with whites in most measures of health in the United States, and very early puberty in Black girls joins this alarmingly long list. Every risk factor for early puberty affects Black girls more than white girls.

One way that Black girls are exposed to even more chemicals than white girls, though, is through the heavy use of hair care products. In 1998, Dr. Chandra Tiwary reported the shocking news that four Black girls, one just 14-months-old, had developed breasts or pubic hair after using hormone-containing hair products. The girls’ pubertal symptoms went away when they stopped using the hair products. A small 2002 study found that, in comparison with white families and immigrant African families, Black-American parents used hormone-containing hair products about four times more frequently on themselves and their children. When I googled “placenta hair care,” I found 95 products for sale. The placenta, mostly coming from sheep, is a hormone factory, producing progestins, estrogens and growth hormones in abundance.

Even if a family never uses personal care products with animal placenta or hormones in them, regular hair care products are loaded with all sorts of chemicals that may pose health risks. “Africa’s Best Kids Organics, No-Lye Organic Conditioning Relaxer System with ScalpGuard” sounds safe, doesn’t it? The Environmental Working Group has a very informative website called Skin Deep Cosmetic Safety Database (www.cosmeticsdatabase.com) where it rates the safety of thousands of personal care products for health effects. One of the categories is a chemical’s potential for disrupting hormones. Out of 78 hair relaxers rated by the group, Africa’s Best is the most dangerous. For those of us who love scents, it is bad news that Skin Deep red-flags all fragrances. “Fragrance” is a catch-all word for 4,000 different chemicals, and one particular fragrance in a product can contain up to 40 chemicals. Big companies reformulate their products as often as every three months, according to an Environmental Working Group research analyst, making it hard for consumers to keep up with which products are safe.

Of the approximately 100,000 synthetic chemicals permeating our environment, 10,000 of them are used in personal care products, and only about 10 percent of those have been tested for safety. The federal government typically relies on chemical manufacturers to do their own testing. Each chemical is tested alone, although humans are exposed every day to hundreds of chemicals that have interacting effects. The U.S. government does not examine whether chemicals we are exposed to affect our hormones, so we can’t look to the government to find out if everyday products are causing girls to reach puberty early.

Other countries have been far more proactive in protecting their citizens. The European Union, for example, banned phthalates in cosmetics in 2003 and in children’s products in 2005. State and local governments do better than the U.S. government. California has banned phthalates in toys and baby products starting in 2009, and other states are taking steps to follow its lead. San Francisco passed a law banning BPA in toys and kids’ products, something that even Europe has not done. Even individual companies are making changes—Deep Rock Water Company in Denver is halting the use of polycarbonate water jugs because they leach BPA.  
 
My own daughter, who is now almost 10, remains delightfully flat-chested. I pack her school lunches in metal thermoses and metal water bottles. But I cringe as I watch her classmates line up for school lunches heated in plastic, and eat and drink food carried from home in plastic containers. Some of the girls have already grown prominent breasts and with all that I have learned, I am worried about their futures. 
 
Susan H. Shane is a biologist and mother. 

Adolescent Marijuana Use Increases Risk of Schizophrenia

first posted 27 October 2010

It turns out that the oft-ridiculed film “Reefer Madness” may contain a grain of truth for a small subset of young marijuana users.  The original 1938 film was entitled “Tell Your Children”, and, indeed, that is exactly what researchers now recommend for kids who intend to use marijuana. New and ongoing research has shown conclusively that marijuana use in adolescence raises the risk of developing a psychotic illness like schizophrenia.  The earlier in life marijuana is used, the higher the risk. A New Zealand study of 1000 people followed from birth to age 26 found that 10% of those who used cannabis before age 15 became schizophrenic versus only 3% of people who rarely, if ever, tried marijuana before age 18.

The evidence for the cannabis-psychosis connection has been building in the medical literature for years. Two studies of siblings published this year (one in Australia, the other in the Netherlands and Belgium) provided the strongest data yet; by using full siblings brought up in the same home, these studies eliminated many of the confounding variables found in other studies.  Although researchers stop short of saying that marijuana causes psychotic illness, they are now certain that it is one of the risk factors contributing to these diseases.  Theresa Moore and colleagues wrote in a 2007 issue of the British medical journal, The Lancet: “there is now sufficient evidence to warn young people that using cannabis could increase their risk of developing a psychotic illness later in life.”  Researchers from the UK and New Zealand comment “Policy makers and law makers should concentrate on delaying onset of cannabis use.”

Heavy users and those whose use extends for a long time also increase their risk of developing psychosis. People who have used cannabis 50 or more times are six times more likely to develop schizophrenia than are non-users.  The 2010 sibling study in Australia and another related study showed that those who used marijuana for six years or longer were at significantly higher risk of having psychotic symptoms or developing a psychotic illness than those who used cannabis for a shorter period of time.  This study found that, when two siblings both use cannabis, the one who has used it for the longest time is at higher risk of psychosis.

Young people who start life at higher risk of developing a psychotic illness are more sensitive to cannabis and its psychotic effects.  Who is at risk? a) children with mentally ill family members; b) those who have experienced prenatal or childhood trauma; c) anyone who has a temporary psychotic reaction (hallucinations, delusions, distorted thinking) when using marijuana; and d) people who live in cities.  The 2010 Holland-Belgium study of siblings showed that people with a genetic risk for psychosis are more sensitive to the psychosis-inducing effects of marijuana, and the combination of genetic risk and cannabis use can lead to psychotic illness. Finally, researchers have found that marijuana use in people already diagnosed with psychotic illness worsens their symptoms.

Some evidence shows that a first psychotic episode in users is associated with higher potency cannabis. The potency of marijuana (concentration of delta-9-THC) in the U.S. has increased over time.  It went from 1.5% in 1980, to about 3% in 1983-1992, to 4.5% in 1997, and to 9.6% in 2007.  

Past misinformation and scare tactics about marijuana led Baby Boomers and following generations to dismiss almost any negative news about the drug.  As parents, this group tended not to worry about marijuana use in their children.  Since it’s true that most people can use marijuana without serious consequences, why make such a big deal about the small number of young people who may be tipped toward schizophrenia by cannabis?  If you are the kid who starts hearing voices, whose thoughts become twisted and non-sensical, who believes you’re being followed by the police...if you are the parent who watches a bright, social child disappear into the darkness, whose hopeful dreams for your offspring’s future are crushed...if you are one of these people, the link between marijuana and psychosis matters.  

Family members attending a NAMI (National Alliance for the Mentally Ill) support group admitted to starting out fairly lackadaisical about their children using marijuana.  However, most of them now tie marijuana to the initial decline in mental health they saw in their kids.  Many of the NAMI parents suspected that their children were “self-medicating” with marijuana.  A 2010 British Journal of Pharmacology paper definitively states that there is “overwhelming” lack of evidence for the self-medication hypothesis.  While studies have shown that marijuana use is not a risk factor for having depression and anxiety, researchers cannot rule out the possibility that some youngsters may use marijuana to self-medicate for these illnesses.  

  

Millions of Americans use marijuana despite its illegal status: 14.4 million had used it in the month before being questioned in a 2007 survey.  Sixty-two percent of the 2.1 million new users each year are under 18.   A global 2008 study by the World Health Organization showed that the U.S. and New Zealand had the highest rates of kids under 15 using marijuana.  Interestingly, by 21 years, 54% of Americans had used marijuana while only 35% of people in the Netherlands, where cannabis is decriminalized, had. Wikipedia reports that the percentage of people who had used cannabis in the last year was twice as high (12.6%) in the U.S. as in the Netherlands (6.1%).  Overall, the U.S. has the highest rates of both legal and illegal drug use in the world.

Update from the scientific literature (Oct. 2017):  https://www.scientificamerican.com/article/link-between-adolescent-pot-smoking-and-psychosis-strengthens/

Another update (May 2018):  https://www.washingtonpost.com/news/posteverything/wp/2018/05/25/feature/legalizing-marijuana-is-fine-but-dont-ignore-the-science-on-its-dangers/?utm_term=.a06c48b750f3

Yet another update (Jan. 2019): https://www.nytimes.com/2019/01/17/health/cannabis-marijuana-schizophrenia.html

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Author's Note on California's Prop 19 (Marijuana Legalization)

I support the passage of Prop 19 on the 2 Nov. 2010 ballot for several reasons.
1) The proposition identifies marijuana as an "adult drug" by setting an age limit of 21 years for marijuana possession.  This fits well with the data showing that youth are at the highest risk from cannabis use.
2) Legalization will permit public health education campaigns to be directed at users and potential users.  The current illegal status of marijuana leads to a "head in the sand" approach where risks are not addressed publicly.
3) The potency of legal marijuana is more likely to be controlled and limited than that of illegal marijuana.
4) Laws prohibiting marijuana have not stopped its use.
5) Criminalizing marijuana has destroyed many lives by incarcerating users and leading to violence associated with the illegal drug trade.
6) The financial costs of incarcerating cannabis users are too high, especially considering the state's budget crisis.
7) Taxing marijuana could provide vitally-needed funds for state and local budgets.