<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div><div><br></div>Wow, I should have know y'all might have a lot to say -- and thank you again each and all for speaking up! This is great!<div><br></div><div>I'm forwarding the note below from a friend here in California, Barbara Roemer, who reads but as yet cannot post to GSBN. </div><div><br><div apple-content-edited="true"> <div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="font-size: 12px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; ">Thanks,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; ">Bruce King</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; "><a href="mailto:bruce@bruce-king.com">bruce@bruce-king.com</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; ">(415) 987-7271</div></span></div></span></div></span><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="font-size: 12px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; ">Twitter: @brucekinggreen</div></span></div></span></div></span><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="font-size: 12px; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; ">blog: bruceking.posterous.com</div></span></div></span></div></span><span class="Apple-style-span" style="font-size: 12px; ">Skype: brucekingokok</span></div> </div><div><br><div>Begin forwarded message:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" color="#000000" style="font: 12.0px Helvetica; color: #000000"><b>From: </b></font><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Barbara Roemer <<a href="mailto:roemiller4@gmail.com">roemiller4@gmail.com</a>></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" color="#000000" style="font: 12.0px Helvetica; color: #000000"><b>Date: </b></font><font face="Helvetica" size="3" style="font: 12.0px Helvetica">January 5, 2012 1:30:43 PM PST</font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" color="#000000" style="font: 12.0px Helvetica; color: #000000"><b>To: </b></font><font face="Helvetica" size="3" style="font: 12.0px Helvetica"><a href="mailto:bruce@ecobuildnetwork.org">bruce@ecobuildnetwork.org</a></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" color="#000000" style="font: 12.0px Helvetica; color: #000000"><b>Subject: </b></font><font face="Helvetica" size="3" style="font: 12.0px Helvetica"><b>concrete context</b></font></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div> </div>Hi Bruce,<div><br></div><div>I'm a recent subscriber to the Greenbuilder list, but obviously can't post. Charles Kenny's article on paving over earthen floors is of great interest to me. I appreciate your posting it and look forward to others' comments. I have an earthen floor, so in the particular, I'm concerned about possible compromised air quality. In a broader perspective, we are natural builders and have helped many people in Northern California put in earthen floors, always with attention to the sealing so they can be cleaned, and to the sealing agent so we're not dealing with VOCs/offgassing. Since all these floors have been well-sealed, I hadn't given any thought to particulates being a problem.</div> <div><br></div><div>It seems to me that dust is certainly related to improper or no sealing, although that doesn't mean we haven't created other air quality issues. But I have never seen insects coming up through an earthen floor that's well-saturated with linseed oil or other oil sealers. Since these floors I'm familiar with in the US have tamped gravel subfloors, it also seems unlikely that hookworms are penetrating both the gravel/fines subfloor and the oiled, tamped clay. I don't doubt that where hookworm and other parasites are eliminated, quality of life in general improves, and in particular on many of the metrics Kenny cites. However, probably some of the improvements he mentions are due to perception: that is, where earthen or "dirt" floors are stigmatized and undesirable, seems natural that people would respond positively to the "improvement" of concrete. If the street is paved, surely it's more passable that a rutted dirt track, but rents are likely to rise both because of the real improvement in the condition of the road as well as because of the perceived improvement of a modern, acceptable material. (I think of the placebo effect in disease treatment being as high as 30% in some studies.) Of course, dust pollution in California's Central Valley is a well-known health hazard, and much of it arises from unpaved farm roads as well as from tilling the soil. It seems to me that the questions raised by the article are interesting, but not necessarily simple to answer.</div> <div><br></div><div>Another consideration is that of unexpected consequences. There is some limited research going on in the US regarding the value of hookworms in the treatment of autoimmune diseases. It's related to the hygiene hypothesis: apparently asthma, allergies, inflammatory bowel disease and other immune diseases are not generally found in people with hookworms and related helminths (Google David Pritchard + Helminths). NPR ran a RadioLab show on the topic a couple of years ago. While it's true that hookworms can result in severe anemia, that's not so in well-nourished populations. Clinical trials on the effect of helminths on autoimmune diseases are just beginning. Right now, no studies are conclusive, but they are being run by credible institutions, including U.C. San Francisco Medical Center. </div> <div><br></div><div>I'm not advocating dirt floors, unsealed and potentially full of parasites, but context may be fairly significant before drawing conclusions. For now, I'm planning another earthen floor, but I'd like to see some testing on hygiene, parasite presence, and VOCs related to indoor air quality on earthen floors as they are currently installed in best practice in eastern and western countries where they are floors of choice rather than those of default. </div> <div><br></div><div>Barbara Roemer</div><div>Nevada City, CA</div><div><br></div><div><div><br></div>-- <br><span style="font-family:Times;font-size:medium"><pre style="text-align:left"><span style="font-family:arial;white-space:normal;font-size:small"><div>
We are silence,</div><div>We are golden,</div><div>We are billion-year-old carbon,</div><div>And we got to get ourselves back to the garden.</div><div> </div><div> -Joni Mitchell<br clear="all">
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