Marnie Chesterton

Today most rubber comes from South Asia, where the South American leaf blight has so far been kept away. I'm Marni Chasterton from the BBC World Service. This is Unexpected Elements.

And I'm joined as ever by a global panel of science journalists. We have Sandy Ong in Singapore. Hello, hello. Hi, Marni. Ni hao. And journalist Lerni Joubert. You used to live in Cape Town, but Lerni, you're now our van life correspondent. Where are you this week? Marni, I am on the wild coast on the eastern side of South Africa, near a place called Port St. John's. Lovely.

So, what we do on Unexpected Elements each week is we take a story from the news and we use that as our jump-off point to discuss a world of interesting science. So, given that I started the show musing about rubber production, let's hear what kicked that off.

Yes, this is the story that the world's largest condom manufacturer, Carex, who make 5 billion condoms a year, plan to raise their prices by 20, 30, possibly more percent. All due to the fact that the supply chain of raw materials continues to be disrupted by the Iran war and the blockade of the Strait of Hormuz.

Sandy, have you heard of the condom crisis? Yeah, actually, partly because Carex, the manufacturer, is based in Malaysia, which is literally on our doorstep. Marni, back to you. Tell me, how has a lack of oil led to this condom crisis? That is exactly what I was wondering. And a lot of condoms are made of natural latex, which is produced from this tree, the Hevia brasiliensis.

Oil comes in because the raw latex is treated with ammonia to preserve it. And the ammonia comes several steps down the line from the refinement of crude oil. It's not the only product that relies on oil and petrochemicals in the manufacturing process. But in unexpected fashion we're going to focus on the most surprising, which to us was condom prices. So, condom price hike and possible shortage, there is our starting point.

Lani, where do you want to take us from here? Well, Marni, it seems there's been a bit of a boom or bust situation down under in Koalaville. Koalas have been in the news quite a lot of late, mostly because their numbers are dropping. According to the IUCN listing, they are regarded as vulnerable. But in 2022, Australian law recognised them as endangered.

But there are some refuges where koalas are doing so well that conservationists have had to turn to prophylactics. When you say prophylactics, please tell me you're talking about condoms for koalas. That would add an interesting spin, but not quite. Really, they're just using the same good old-fashioned hormone treatment that liberated us back in the 1960s. Specifically, they're using an implant containing a synthetic hormone that mimics progesterone.

It's not that new in koala management though. Apparently some populations have been kept in check for at least 20 years in this sort of method from what I can find. I'm a little bit confused though, because if koala populations are vulnerable, it seems weird to be giving koala birth control to the ones that are thriving, no?

Kyllä, se näyttää hieman yksinkertaiselta, mutta asia on se, että koalat ovat todella hyvät syötäjät. He pystyvät kasvamaan vain muutamia yksilöitä eukalyptoista. Ja Suomalaisessa Estä-Australiassa he ovat yliopistoneet manna-kummi-eukalyptoista paikoillaan. Ja jos se tapahtuu, se tappaa koalaa ja se voi edistää isoja koalapopulaita, jotka ovat syötäneet.

Ne ovat yksityiskohtaisia näissä pienissä alueissa. Joten tämä on yksi tehtävä, jotta voimakkaus ei pysy. Kyllä, se on melkein se, mitä tapahtuu. Mutta ainakin on helpompaa antaa koalaan kontraseptiivisen implantin, kuin antaa afrikkalaisen elokuvan, joka on sama kuin syrjintäkontrollin pilli.

Yes, I'd say that that's an interesting job. Does anyone have to do that? I mean, I imagine it's going to be a bit harder to just grab hold of an elephant. You've got bigger bodies, bigger appetites, bigger territories. Bigger feet to stomp you with and also a bigger nose to smack you with.

Managing elephant populations is a real hot button issue over here in southern Africa, because very few populations can roam as widely as they need to, since they're all corralled inside closed off reserves. And as with the koalas, if their numbers outpace what the landscape and the vegetation can support, they'll also end up starving. Usually numbers are managed with culling or relocating.

Kulling is horribly cruel. You know, elephants are highly intelligent, they have sophisticated cultures, really sophisticated social structures. And then of course relocating is super expensive. Okay, so contraception is much easier in theory. In practice, how do they do it?

No, minulla oli Dr. Audrey Delsink, joka on Suomalaisen Suomalaisen yliopistossa Afrikassa. Hän kertoi minulle metodin, jonka he suosittelevat ja suosittelevat. Kaikki, mitä tarvitset, on käynti, jonka järjestäjä ja kestävä käynti, ja jonka järjestäjä, jonka järjestäjä ja kestävä käynti.

Jotkut jättävät kivun, jolla on ensimmäinen kivu. Jotkut heittävät hänet kivuun, joka käsittelee taitoja ja purpaa kivua, jotta hänet tietää, millainen kivu on. Jotkut jättävät kivun, jolla on ensimmäinen kivu, jota hänet tietää, millainen kivu on.

Kyllä, se on hieno kysymys. He ovat yrittäneet tätä. He antoivat joitakin vanhempien eläinten visektomia, ja he halusivat nähdä, onko animali- tai ryhmätyötä muuttunut. Ja se ei ollut. Joten kysyin Dr. Dalsinkista, miten nämä kaksi asiaa verrattuna. Ja hän sanoi, että viimeisen eläinten visektomien kohdalla se toimii noin 130 euroa eläinten per vuosi.

Vesektominen koulutus on todella kalliikkaa. Ja oikeastaan veterinaarien taitoja on erittäin erilaisia. Joten se tulee hieman liian haastavaa. Hieman helpompaa. Sandy, missä haluat ottaa meitä seuraavaksi? Minulla on hieman mysterytä sinulle tänään. Se ei ole täysin selvää, miten tämä liittyy kondomille. Mutta pysyäni minulle. Toivon, että se on tarpeeksi. Minä olen täällä mysterytä, joten menetään.

So some time ago, a multidisciplinary team of researchers from the University of Michigan were working together on a project. And they were trying to figure out how many microplastics people in their city were inhaling while outdoors. Just to be clear, a microplastic is a piece of plastic that's smaller than... About five millimeters, which is roughly the size of a pencil eraser. But that's the high end of the scale. They actually go down to much, much smaller than that.

Mikroplastiitit ovat löytyneet kaikessa ja kaikessa. Ihmisissä ne ovat löytyneet sydän, sydän, rauha, kärsikot, placenta, kärsikot, ja niin edelleen. Lisäksi tutkijat ovat löytäneet mikroplastiitit paikoissaan Mariana-trenkissä, joka on yksi laajimmista osista maata, ja myös Mount Fujiin yläpuolella.