Environmental Pollution, the thread...

[DragonsFriend]

Re: Environmental Pollution, the thread...

If we do usher in an instinction even we will never do that again as we will be the ones extinct. The Earth will heal and life (without us) will go on.

[thalassa]

Re: Environmental Pollution, the thread...

We do not struggle to save the Earth, but rather we struggle to save ourselves and the habitat in which we are comfortable. It seems a bit selfish and at the same time grandiose of us to believe that we are saving the Earth.

On one hand, yes.

On the other hand, knowing what we know about how systems work over all, its a bit delusional to think that, given our sheer numbers and technological capabilities (which tend to magnify our sheer numbers), we are incapable of ushering in the another great extinction event.

[ThePaganMafia]

Re: Environmental Pollution, the thread...

[DragonsFriend]

Re: Environmental Pollution, the thread...

At the K/T boundary (65 million years ago) the temperature of the Earth was 6 to 14C higher than it is today. Ocean levels were over 300 meters higher than they are today. There were no people around to notice the changes that were taking place. The Methane levels were considerably higher than today and the CO2 levels rapidly changed to much higher levels than we have today. This along with a large asteroid strike caused much of the extinction that took place on land and in the water. Mankind did not cause those dramatic changes in atmospheric temperatures but now we are here and trying to understand what is going on. It seems to be a bit egocentric to believe that mankind is a direct cause of things that have happened before when we weren't around. I do believe the climate is changing. It has been getting warmer since the last Ice age and will likely continue to warm until the next Ice Age or until, as the Sun ages, the amount of heat received by the Earth from the slowly dying Sun burns the earth away. (as the sun ages it will grow and release more heat than it has in the past) We are at the Sun's middle age now and in around 4.5 billion years it will either engulf the Earth completely or at least vaporize it.
Tomorrow the Yellowstone caldera could erupt sending the Earth into a "nuclear" winter that would take decades to recover from. That would take the human population out of the equation and return the Earth to a prehistoric level of equilibrium. I believe it is a good idea to limit CO2 production and I believe it will be necessary to prohibit all combustion uses of all kinds. It might even get to the point where we have to limit the Earths exposure to the Sun's heat to prolong our habitat but no matter what we do the Earth is one day going to fail to be a livable habitat for us.
For now we are reliant on the Earth and its processes to survive but the Earth is not reliant on us. Evolution will continue even if we destroy ourselves and the Earth will adapt and grow quite well without us. We will not be missed by the animals left after us and neither will the animals and plants that we destroy with ourselves. We do not struggle to save the Earth, but rather we struggle to save ourselves and the habitat in which we are comfortable. It seems a bit selfish and at the same time grandiose of us to believe that we are saving the Earth.

[DanieMarie]

Re: Environmental Pollution, the thread...

Green technologies are finally starting to pay off. I argue about this to no end with my brother (who currently works in the oil industry, but does not have an apprenticeship that is specifically tied to oil or gas). At some point, we're going to finally move past fossil fuels, and it's already starting.

[thalassa]

Re: Environmental Pollution, the thread...

Climate change:

An interesting study-- https://www.washingtonpost.com/news/...lanets-future/
(and the actual study) http://www.atmos-chem-phys.net/16/37...iscussion.html

The 66million year precedent-- https://www.washingtonpost.com/news/...cientists-say/

Economic growth "decoupled" from carbon emissions for the first time in decades-- https://www.washingtonpost.com/news/...-failed-again/

[thalassa]

Re: Environmental Pollution, the thread...

cool bit on atmospheric aerosols (naturally occurring and manmade): http://earthobservatory.nasa.gov/Features/Aerosols/

[magusphredde]

Re: Environmental Pollution, the thread...

A lot of zinc has been put into the environment since their use started ... Some weigh as much as 45 pounds (about 20 kilos) each ... http://www.rotometals.com/product-p/...FYVqfgoddosG0w ... And not by ust the boating and shipping industry http://corrosion-doctors.org/Corrosi...CP-History.htm

[thalassa]

Re: Environmental Pollution, the thread...

I wonder how much zinc has been added to the oceans and lakes from "sacrificial" zincs on the hulls of boats and ships ???

Probably about as much as what comes from sunscreen off swimmers.

[magusphredde]

Re: Environmental Pollution, the thread...

I wonder how much zinc has been added to the oceans and lakes from "sacrificial" zincs on the hulls of boats and ships ???

[DanieMarie]

Re: Environmental Pollution, the thread...

How do you know zinc shows no evidence of causing environmental harm to coral reefs? Where is the data? Where are the studies?

We have plenty of evidence that zinc can be and is harmful to people and to the rest of the environment. Because the dose makes the poison.



Now, is all this zinc coming from sunscreen in wastewater? Probably not. Zinc is something that *should* be removed during the process of treating it. But people go to the beach that waterproof sunscreen has to go somewhere. Taken by itself, zinc in sunscreen is probably extremely negligible in the environment. But, its a contributory affect---its one more route for zinc to enter an environment in a way that it was not occuring without human involvement (by far, the problem from zinc comes from mining and smelting). Zinc in particular is a fish neurotoxin (when the dose is right) and is taken up readily in aquatic environments.


If one has to choose between zinc and BP-2, is zinc less damaging to a very specific part of the environement? Probably. But we don't know that until its been studied.

I'm not trying to pick on you here. I'm trying to say that there are always, always, always tradeoffs. Nothing is safe. Safety is a relative term. Harm is a relative term. We need better data (which is expensive) to make the decision that mitigate harm as much as possible and ensure safety--for everyone, human and non--as much as possible. But the science we use to make those decisions needs to be sound. I'm a firm believer in the precautionary principle. But once again, it comes down to dose.

Gotcha. Also, I didn't think you were trying to pick on me. I really appreciate the time you've taken to explain the data better. Stuff like that is really helpful for those of us who don't always totally understand the science and have to rely on the layman's terms the press presents (which aren't always correct).

[anunitu]

Re: Environmental Pollution, the thread...

There is the issue of those TINY plastic beads used in facial scrubs and other places showing up in water supply's.

[thalassa]

Re: Environmental Pollution, the thread...

Interesting. But still, I don't know about there, but here there are a lot of sunscreens that contain zinc and other ingredients that show no evidence of causing harm. Wouldn't it be just better to air on the side of caution and use those instead?

Personally, I usually forget to wear sunscreen anyway because I don't burn or tan. I know it's not the best, but when nothing happens to my skin in the sun, it's hard to remember.

How do you know zinc shows no evidence of causing environmental harm to coral reefs? Where is the data? Where are the studies?

We have plenty of evidence that zinc can be and is harmful to people and to the rest of the environment. Because the dose makes the poison.

Zinc enters the air, water, and soil as a result of both natural processes and human activities. Most zinc enters the environment as the result of mining, purifying of zinc, lead, and cadmium ores, steel production, coal burning, and burning of wastes. These activities can increase zinc levels in the atmosphere. Waste streams from zinc and other metal manufacturing and zinc chemical industries, domestic waste water, and run-off from soil containing zinc can discharge zinc into waterways. The level of zinc in soil increases mainly from disposal of zinc wastes from metal manufacturing industries and coal ash from electric utilities. Sludge and fertilizer also contribute to increased levels of zinc in the soil. In air, zinc is present mostly as fine dust particles. This dust eventually settles over land and water. Rain and snow aid in removing zinc from air. Most of the zinc in lakes or rivers settles on the bottom. However, a small amount may remain either dissolved in water or as fine suspended particles. The level of dissolved zinc in water may increase as the acidity of water increases. Fish can collect zinc in their bodies from the water they swim in and from the food they eat. Most of the zinc in soil is bound to the soil and does not dissolve in water. However, depending on the type of soil, some zinc may reach groundwater, and contamination of groundwater has occurred from hazardous waste sites. Zinc may be taken up by animals eating soil or drinking water containing zinc. Zinc is also a trace mineral nutrient and as such, small amounts of zinc are needed in all animals.

sauce (crud, I forgot to link it and now I can't find the link again...it was from either the epa or cdc)

Now, is all this zinc coming from sunscreen in wastewater? Probably not. Zinc is something that *should* be removed during the process of treating it. But people go to the beach that waterproof sunscreen has to go somewhere. Taken by itself, zinc in sunscreen is probably extremely negligible in the environment. But, its a contributory affect---its one more route for zinc to enter an environment in a way that it was not occuring without human involvement (by far, the problem from zinc comes from mining and smelting). Zinc in particular is a fish neurotoxin (when the dose is right) and is taken up readily in aquatic environments.


If one has to choose between zinc and BP-2, is zinc less damaging to a very specific part of the environement? Probably. But we don't know that until its been studied.

I'm not trying to pick on you here. I'm trying to say that there are always, always, always tradeoffs. Nothing is safe. Safety is a relative term. Harm is a relative term. We need better data (which is expensive) to make the decision that mitigate harm as much as possible and ensure safety--for everyone, human and non--as much as possible. But the science we use to make those decisions needs to be sound. I'm a firm believer in the precautionary principle. But once again, it comes down to dose.

[DanieMarie]

Re: Environmental Pollution, the thread...

Interesting. But still, I don't know about there, but here there are a lot of sunscreens that contain zinc and other ingredients that show no evidence of causing harm. Wouldn't it be just better to air on the side of caution and use those instead?

Personally, I usually forget to wear sunscreen anyway because I don't burn or tan. I know it's not the best, but when nothing happens to my skin in the sun, it's hard to remember.

[thalassa]

Re: Environmental Pollution, the thread...

Also, did everyone catch the news on sunscreen last week (or maybe it was the week before that)? Studies show that chemicals found in a lot of sunscreen are contributing to coral reef bleaching:

http://time.com/4080985/sunscreen-coral-reefs/

http://oceanservice.noaa.gov/news/feb14/sunscreen.html

Although BP-2 may be a contaminant on coral reefs, its environmental toxicity to reefs is unknown. This poses a potential management issue, since BP-2 is a known endocrine disruptor as well as a weak genotoxicant. We examined the effects of BP-2 on the larval form (planula) of the coral, Stylophora pistillata, as well as its toxicity to in vitro coral cells. BP-2 is a photo-toxicant; adverse effects are exacerbated in the light versus in darkness. Whether in darkness or light, BP-2 induced coral planulae to transform from a motile planktonic state to a deformed, sessile condition. Planulae exhibited an increasing rate of coral bleaching in response to increasing concentrations of BP-2. BP-2 is a genotoxicant to corals, exhibiting a strong positive relationship between DNA-AP lesions and increasing BP-2 concentrations. BP-2 exposure in the light induced extensive necrosis in both the epidermis and gastrodermis. In contrast, BP-2 exposure in darkness induced autophagy and autophagic cell death. The LC₅₀ of BP-2 in the light for an 8 and 24 h exposure was 120 and 165 parts per billion (ppb), respectively. The LC₅₀s for BP-2 in darkness for the same time points were 144 and 548 ppb. Deformity EC20 levels (24 h) were 246 parts per trillion in the light and 9.6 ppb in darkness.

(sauce --its pay to play, and I don't have springer access right now, so I can't read the whole thing to evaluate their methodology, etc)

I'm guessing these are lab studies, so this is likely done in a tank rather than an environmental study. The way the abstract reads, the coral was exposed to BP-2 at varying levels for different periods of time--an 8 or 24 hour treatment. This isn't exactly real-world data, its straight toxicology data. In which case, how big was the sample size? How many trials were there? What were lab conditions? What was the light wattage? Did the light intensity change as it would in a daytime environment, or was it constant? Was the light intensity variable for different depths in different treatments? Basically, did the amounts of light used look and act like sunlight would to a coral 10-20 or 30-40 feet below the ocean? How was potential contamination from other sources controlled? Obviously, from *when* they introduced this (during the larval stage and to individual cells that have been harvested) it is a developmental issue...so, how does BP-2 affect adult coral? What about corals of other species--why was this one chosen?

But most importantly...How much BP-2 is actually in our wastewater, and (by the time it makes it out to sea) how much BP-2 is actually found at coral reefs anyway? Its great to know how much of X kills or damages an organism or its reproductive capablities. But if the amount that it takes isn't anywhere close to what is found in the system, its a bit of a moot point. AND from a media/public education perspective, stuff like this tends to get taken utterly out of context.