wrote:
John I cannot work with rocks because they so often catch my mower.

I do agree about earthworms and hope that the asphalt shingles increase
the earthworm population.

But I suspect the carcinogen claim or claim of bad chemicals in the
shingles are false claims. People think there are bad chemicals but
have no data.

I suspect that any chemicals in the roof shingles are broken down by
the time they become degraded into the soil.

Can you list, John, a list of the top five bad chemicals in these roof
shingles that you claim would end up in the soil. Again, I would
estimate that all the chemicals would be degraded and altered by the
time the shingles became soil.

[snip]

Excuse me, John, but in case there is anyone still unswayed, a good ref
to show that carcinogens (what I said earlier - heavy metals) are in
shingles, is:

Van Metre, P.C., Mahler, B.J. 2003. The contribution of particles
washed from rooftops to contaminant loading to urban streams.
Chemosphere 52:10 pp. 1727-1741

Now, everyone, please. Shingles are a fantastically bad idea. I hope no
one is considering this idea. Fer chrissake, stop this madness.

D

Now there is another evidence that John is mistaken about asphalt and
bad chemicals although it is not a fine example it is an example none
the less. What I am talking about is the growing propensity of plants
near asphalt roads. Perhaps the propensity is that the asphalt road
provides a large mulch for the trees alongside the road. And whether
any fruit from those trees next to an asphalt road have bad chemical
contents, which I suspect do not.

I think the trouble here is that John and many others are working from
a opinion and belief but not working from actual science research. They
opine that asphalt has bad chemicals and they opine that those bad
chemicals will transfer into the tree and its fruit. But I get the
sense that asphalt roads and asphalt roof shingles that are untreated
have mostly a great benefit to any plant lucky enough to have them as a
mulch. I suspect that by the time the shingles degrade into the soil
that they enrich the soil.

So we need a real science testing and research and not everyone with
their bias opinion saying bad chemicals.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

I have not seen that article but I would guess from the title of
"particles washed" they are referring to those tiny pieces of gravel
and stones that the shingles have on the surface and those tiny stones
are never a threat to plants. I would guess that as the gutters of
roofs with asphalt shingles are mostly the accumulation of those tiny
stones that deteriorate from the shingles and accumulate in the gutter.
And I would guess that the report is because those tiny stones present
a contaminant in the urban environment.

Can Dano post a paragraph about that article so that we can see what
specifically is the contaminant.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

In article . com, wrote:

[...]

I think the trouble here is that John and many others are working from
a opinion and belief but not working from actual science research. They

gentle, inoffensive mode

No, Archie, that's your practice. Facts don't matter to you, only your
predetermined conclusions. If the facts or observations contradict you, they
are obviously wrong. "They're all out of step but Jim."

/

Abstract

Rooftops are both a source of and a pathway for contaminated runoff in
urban environments. To investigate the importance of
particle-associated contamination in rooftop runoff, particles washed
from asphalt shingle and galvanized metal roofs at sites 12 and 102 m
from a major expressway were analyzed for major and trace elements and
PAHs. Concentrations and yields from rooftops were compared among
locations and roofing material types and to loads monitored during
runoff events in the receiving urban stream to evaluate rooftop sources
and their potential contribution to stream loading. Concentrations of
zinc, lead, pyrene, and chrysene on a mass per mass basis in a majority
of rooftop samples exceeded established sediment quality guidelines for
probable toxicity of bed sediments to benthic biota. Fallout near the
expressway was greater than farther away, as indicated by larger yields
of all contaminants investigated, although some concentrations were
lower. Metal roofing was a source of cadmium and zinc and asphalt
shingles a source of lead. The contribution of rooftop washoff to
watershed loading was estimated to range from 6 percent for chromium
and arsenic to 55 percent for zinc. Estimated contributions from
roofing material to total watershed load were greatest for zinc and
lead, contributing about 20 and 18 percent, respectively. The
contribution from atmospheric deposition of particles onto rooftops to
total watershed loads in stormwater was estimated to be greatest for
mercury, contributing about 46 percent.

[ ... ]

4.2.2. Roofing material

[ ... ]

The asphalt-shingle roofing material sampled for this study was found
to be a source of lead and possibly mercury. Lead concentrations and
yields were significantly higher in particles washed from asphalt
shingle roofs than in those washed from metal roofs. Asphalt shingle
roofs may also be a source of mercury. Concentrations of mercury from
asphalt shingle roofs were significantly higher than concentrations
from metal roofs, but yields of mercury were not. However, in those
cases where mercury yields from asphalt shingle roofs did exceed those
from metal roofs, the difference was much greater (3-8 times greater)
than when the yields from metal roofs exceeded those from asphalt
shingle (1-2 times greater). Regional atmospheric fallout, generally
thought to be the major source of mercury in the environment ([Swain et
al]), does not explain the elevated concentrations of mercury often
seen in urban sediments, thus the possibility that asphalt shingle
roofs may be a source of mercury to the urban environment is intriguing
and warrants further investigation.

5. Summary and conclusions

[ ... ]

The relative contributions of atmospheric deposition versus roofing
material to yields from rooftop runoff were also evaluated. Lack of a
roofing material source indicated that PAH, arsenic, chromium, and
copper were from atmospheric sources. Nickel was also dominantly from
atmospheric sources, however, about 40 percent of the lead, 37 percent
of the zinc, and 16 percent of the cadmium in rooftop runoff (median
values) were determined to come from roofing materials, with the
remainder coming from atmospheric deposition. The possibility that
asphalt shingle roofs are a significant source of lead to urban
waterbodies has not, to our knowledge, been reported previously. Some
mercury may also be contributed by asphalt shingle roofs.

HTH,

D

"Dano" writes:

Now, everyone, please. Shingles are a fantastically bad idea. I hope no
one is considering this idea. Fer chrissake, stop this madness.

There's a reason why old shingles are supposed to be disposed of as
hazardous waste.

(Don't a few old types contain asbestos?)

There are several kinds of plastic mulch commercially available without
unnecessary risks.

Dano wrote:
Abstract

Rooftops are both a source of and a pathway for contaminated runoff in
urban environments. To investigate the importance of
particle-associated contamination in rooftop runoff, particles washed
from asphalt shingle and galvanized metal roofs at sites 12 and 102 m
from a major expressway were analyzed for major and trace elements and
PAHs. Concentrations and yields from rooftops were compared among
locations and roofing material types and to loads monitored during
runoff events in the receiving urban stream to evaluate rooftop sources
and their potential contribution to stream loading. Concentrations of
zinc, lead, pyrene, and chrysene on a mass per mass basis in a majority
of rooftop samples exceeded established sediment quality guidelines for
probable toxicity of bed sediments to benthic biota. Fallout near the
expressway was greater than farther away, as indicated by larger yields
of all contaminants investigated, although some concentrations were
lower. Metal roofing was a source of cadmium and zinc and asphalt
shingles a source of lead. The contribution of rooftop washoff to
watershed loading was estimated to range from 6 percent for chromium
and arsenic to 55 percent for zinc. Estimated contributions from
roofing material to total watershed load were greatest for zinc and
lead, contributing about 20 and 18 percent, respectively. The
contribution from atmospheric deposition of particles onto rooftops to
total watershed loads in stormwater was estimated to be greatest for
mercury, contributing about 46 percent.

[ ... ]

4.2.2. Roofing material

[ ... ]

The asphalt-shingle roofing material sampled for this study was found
to be a source of lead and possibly mercury. Lead concentrations and
yields were significantly higher in particles washed from asphalt
shingle roofs than in those washed from metal roofs. Asphalt shingle
roofs may also be a source of mercury. Concentrations of mercury from
asphalt shingle roofs were significantly higher than concentrations
from metal roofs, but yields of mercury were not. However, in those
cases where mercury yields from asphalt shingle roofs did exceed those
from metal roofs, the difference was much greater (3-8 times greater)
than when the yields from metal roofs exceeded those from asphalt
shingle (1-2 times greater). Regional atmospheric fallout, generally
thought to be the major source of mercury in the environment ([Swain et
al]), does not explain the elevated concentrations of mercury often
seen in urban sediments, thus the possibility that asphalt shingle
roofs may be a source of mercury to the urban environment is intriguing
and warrants further investigation.

5. Summary and conclusions

[ ... ]

The relative contributions of atmospheric deposition versus roofing
material to yields from rooftop runoff were also evaluated. Lack of a
roofing material source indicated that PAH, arsenic, chromium, and
copper were from atmospheric sources. Nickel was also dominantly from
atmospheric sources, however, about 40 percent of the lead, 37 percent
of the zinc, and 16 percent of the cadmium in rooftop runoff (median
values) were determined to come from roofing materials, with the
remainder coming from atmospheric deposition. The possibility that
asphalt shingle roofs are a significant source of lead to urban
waterbodies has not, to our knowledge, been reported previously. Some
mercury may also be contributed by asphalt shingle roofs.

HTH,

D

Instead of using the words "possibly mercury" and "may also be a source
of mercury" why did not these researchers simply take the time to
chemically analyze the asphalt shingles for mercury to determine if
they contain mercury content. Why not be direct and simple and
straightforward instead of filling a report with "possibly" "maybe"
"unsure". Why did not the above researchers analyze asphalt shingles
and determine positively and definitely if they contain mercury and
even go to some homes who have extra shingles laying about and happy to
donate to a research and find out if they contain mercury.

I am amazed of the sloppy character of modern research reports such as
the above. Where they fail to do the most direct and straightforward
thing of actually determining whether new asphalt shingles at the store
contain mercury.

I am assuming that asphalt shingles are the endproduct of byproduct of
petrol refineries and they take the black endproducts and raw petrol
and make asphalt. Now I maybe mistaken in that these asphalt shingles
are made from coal. I know that coal contains mercury. I do not know if
raw petrol contains mercury, or mercury above normal concentrations of
the environment.

So why did not the researchers above simply do a direct testing of new
asphalt shingles to verify if they contain a sizeable amount of
mercury.

Ditto for the lead. I do not know if coal or even petrol contains
sizeable amounts of lead.

As far as I know, plants do not intake either lead or mercury and the
environment has minute parts of lead and mercury almost every spot of
earth.

So, now, did the researchers above compare places where they do not use
asphalt shingles or metal roofs with places that do? Because it may
well turn out that places that do not use asphalt or metal roofing have
a higher mercury and lead in their environment than places that use
asphalt and metal roofing. So the above research seems lackadaisacal on
that front.

And finally, although I did not see the full report, only the above 3
paragraphs, there was no emphasis on parts per billion of ambient
metals in the normal environment. If we are talking about so tiny
amounts and when someone says in the above report of a 3 to 8 times
greater amount, well if the amount is so tiny in the first place then a
3 times greater is still tiny. So there is a misleading of the data
amounts in the above report.

All in all, the above is not direct and sloppy and crude. I forgot who
published it, but I doubt that a magazine like SCIENCE or NATURE would
publish it.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

And I would like to suggest a few major culprits that are not the roofs
of asphalt nor sheet metal. Culprit (1) is the automobile and other
vehicles which contain alot of lead for the wheel alignment, sometimes
those lead balances fall off onto the side of the road and present alot
of lead pollution into the environment not to mention the brake system
possibly leaking lead into the environment. And perhaps mercury exists
on automobiles which leaks into the environment. Culprit (2) is that of
guns and pistol ammunition is often lead and so if a person shoots off
some ammo or even just drops it near a building then those researchers
mistakenly attribute the roofs as the source of lead. Culprit (3) the
mercury could be from some other products close to houses and buildings
such as electrical switches of mercury or thermometers and because they
are close to buildings that the researchers mistook the source as being
from the roof whereas it was from the human activity around the
buildings.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

"Dano" wrote in
oups.com:

Abstract

....then a buncha stuff.

Ok, nice article. One important difference between what that research
looks at, and what Mr. Plutonium is doing, is the article seems to be
discussing runoff and effects on watershed, not uptake by plants. It is
important to prevent water supplies from being contaminated, because
water is directly ingested, Archie's question is, do plants take the
chemicals up?

Sean

wrote in
ups.com:

Now there is another evidence that John is mistaken about asphalt
and bad chemicals although it is not a fine example it is an
example none the less. What I am talking about is the growing
propensity of plants near asphalt roads. Perhaps the propensity is
that the asphalt road provides a large mulch for the trees
alongside the road. And whether any fruit from those trees next to
an asphalt road have bad chemical contents, which I suspect do
not.

Since I live in a dry climate, I believe I can provide a reason why
there is greater plant growth near roads. Well, two reasons.

1) Runoff from the road surface can double the amount of effective
rainfall a short distance from the road. That can make a big
difference in available water.

2) The fence that keeps grazers away from the road prevents the
plants from being converted to cow biomass. This can be very marked
in some areas, especially where ranching is practiced.



I think the trouble here is that John and many others are working
from a opinion and belief but not working from actual science
research. They opine that asphalt has bad chemicals and they opine
that those bad chemicals will transfer into the tree and its
fruit. But I get the sense that asphalt roads and asphalt roof
shingles that are untreated have mostly a great benefit to any
plant lucky enough to have them as a mulch. I suspect that by the
time the shingles degrade into the soil that they enrich the soil.

So we need a real science testing and research and not everyone
with their bias opinion saying bad chemicals.


I mistrust your confidence, there are a huge number of organic
compounds in asphalt, most of them not studied for plant uptake.
Most of them are likely very similar to humus compounds, and nothing
to worry about, but even though plants tend to be rather picky about
what they take up, there is the chance that your tomato plant may
have some harmful chemicals in it that while not hurting the plant,
may cause eventual illness in people.

You could try to measure uptake, you would have to grow something
with and without asphalt based mulches, and test them for
differences.

Asphalt is "mostly inert" but that doesn't mean that it is
"completely harmless".

Sean

wrote in
ups.com:



Dano wrote:


Wow. Fantastically bad idea.

1. All that absorbed heat will affect plant tissue near shingles.
2. Heavy metals in manufacture.
3. Gas exchange modification.
4. Other mulches return nutrients to the soil (try, say, 8 in, of
straw, or cardboard and grass clippings).
5. You'll look like a kook.

Really. Natural mulches, please.

D

Tar paper pots that many plants come in. Take tar-paper pots to
each of your above and see how silly and stupid is your attitude
and argument.

Tar paper pots? I don't believe that I have seen these, and an
internet search didn't find anything. Most of the results involved
putting tar paper down on your basement when you grow pot. Searching
for "tar paper pot" only found one site. I am familiar with a couple
of types of peat based pots, are they what you refer to?

Sean

Well the research study should start-off and begin with a thorough
chemical content of the 10 most widely sold brands of asphalt roof
shingles. If it is found that they contain no lead, no mercury, no
selenium, no arsenic or parts per billion that is less than ambient
soil then much or most of the research would already be done. The logic
is that if the shingles when bought new at the store do not contain bad
chemicals more than the ambient soil then they are harmless.

Also, a independent research test should test whether the plastic bags
and plastic containers and plastic cups all derived from petrol stocks
that the asphalt shingles are derived, tested for atoms of mercury,
lead etc that the above tests for. Because I would not be surprized in
the least bit that my Tupperware and plastics in my kitchen contain
atoms of mercury, lead that the ambient soil contains in parts per
billion.

As Sean started his above post by saying that plants thrive best near
the roads in his dry climate is observational evidence that plants like
asphalt and is in agreement with my observations that they like asphalt
roads and they like asphalt roof shingles as mulch. Observation is
proof that plants like asphalt. As to whether they intake harmful
chemicals due to the proximity of asphalt is an open research
question.

And whilst on this subject, has anyone tested the produce of California
compared to other states in that cars and vehicles are one of the
greatest single polluters and given the numbers of autos in California
in close vicinity to their farm produce and considering the dry desert
climate of California that those chemicals would build up in the soils.
So I would suspect that the load of bad chemicals would be higher in
California produce than in produce from say Oregon or Washington state.
It is one of those things that the closer one is to alot of humans and
human activity has the highest chances of pollutants and contaminants.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies

Archimedes Plutonium wrote:
But I suspect the carcinogen claim or claim of bad chemicals in the
shingles are false claims. People think there are bad chemicals but
have no data.

Pitch has long been used by coopers to seal water casks, and is still in
use by many orchardists to seal pruning wounds on fruit trees, so I don't
expect anyone is going to drop dead any time soon through either of these
uses. Most of us spend much of our life inhaling the vapours given off by
hot pitch slowly baking in the summer sunshine as we drive along streets and
highways. This is not to say the risk this poses is diminished one iota just
because everyone is doing it. With the realisation that many risk factors
are cumulative, others may choose not to invite any additional risk -- no
matter how small it may be -- through needlessly introducing pitch to their
organic gardening. That you have chosen otherwise is not of my concern, but
in your post you failed to indicate any cognizance of disregarding the risks
here. I made amends for your omission in my response by drawing attention to
the known toxins in tar to give balance to your endorsement of using such
roof tiles in the garden. While mulching is an excellent idea, for some
people there may be preferable alternatives than the one you have
recommended.

(Both arsenic and chloroform were common ingredients in popular cold
medications until their carcinogenic properties were recognized, and I'd
post a warning about these chemicals were someone to endorse their usage
nowadays, too.)

Can you list, John, a list of the top five bad chemicals in these roof
shingles that you claim would end up in the soil. Again, I would
estimate that all the chemicals would be degraded and altered by the
time the shingles became soil.

It would have taken you far fewer keystrokes to find this out for
yourself on google, instead of trying to get others to do every bit of
homework for you.

Now what was that old adage? -- You can point a twit to google but you
cannot make him click. Something like that.
--
John Savage (my news address is not valid for email)

wrote in
oups.com:

As Sean started his above post by saying that plants thrive best
near the roads in his dry climate is observational evidence that
plants like asphalt and is in agreement with my observations that
they like asphalt roads and they like asphalt roof shingles as
mulch. Observation is proof that plants like asphalt. As to
whether they intake harmful chemicals due to the proximity of
asphalt is an open research question.


Well, actually, plants do just as well next to a concrete road as an
asphalt road, so it isn't the asphalt.

Sean

Hi Sean, and you are probably aware that you outlined a ready made
and somewhat simple research project. We know if a road is asphalt or
concrete and we have thousands of roads to be able to test.

One of my claims for asphalt is that it is a soil conditioner since it
is acidic and would improve a alkaline soil pH. Correct me if I am
wrong but I suspect most every concrete is alkaline due to the lime
added to concrete but whether road concrete has lime added is unknown
to me.

Anyway it would be an easy and exciting, mostly exciting, science
research project to see what plants thrive next to asphalt roads
compared to concrete roads and to find out whether my claim of soil
conditioning by asphalt improves alkaline pH soils such as here in
South Dakota. One of the reasons that my raspberries love the tar roof
shingles as a mulch is my hunch that the tar adds acidity to the soil.
So if plants on the East Coast with their acid soils should do less
well if asphalt roads are nearby than if concrete roads are nearby and
here in South Dakota plants would do better near asphalt than near
concrete. Provided of course that asphalt and concrete contribute to
the soil pH.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies