At that density, you either are long dead from a cholera epidemic, or have a proper sanitation system already in place for decades, rendering this system completely irrelevant for the application being proposed - to provide a "waste disintegrator" for those without plumbing.

56000 people per square mile is about 3 times the density of São Paulo (where I live - about 7500/km2), which is slightly larger than New York's. Let's say it's 4 NYC's one on top of the other.

Can you imagine New York without sanitation? Me neither.

The article is misleading in using the world "toilet" - the serious problem it addresses is sewage, not toilets.

I don't know, but I wouldn't answer "of course not" right away, as you seem to assume. How do these people currently cope?

My point was not that everyone should do as my grandfather's brother, twenty years ago. I'm just wondering why we suddenly need so much technology to solve a problem that's always been with us and that didn't use to be so terrifying.

I'm wondering if we're afraid of "human waste" a little more than we should? I'm wondering if maybe there are simpler solutions that would scale a lot more, be a lot cheaper and a lot less disruptive than getting everyone to defecate in a microwave oven. (How do you build the devices? How do you get them to the people who will be using them? How do you make people use them? How to you maintain them? How do you replace them when they're broken? What do you do with the broken ones...?)

I read a story some time ago (on HN maybe?) about how very simple advice had tremendous effects on people's health. Telling people to wash both hands after going to the bathroom, for instance, instead of just the one they use to clean themselves, yielded incredible results.

I may be wrong, but this project, as described in the original article, doesn't sound right.

Have a look at some of the health problems that come up due to the fact that around 6-700 million people in india defecate openly. http://en.wikipedia.org/wiki/Water_supply_and_sanitation_in_...

"In India there are 700 million people who do not have access to safe and hygienic toilets. The waterborne diseases this causes kill 500,000 children every year, mostly from diarrhea,"

http://www.ctv.ca/CTVNews/Health/20071102/toilet_summit_0711...

While yes the proposed solution does sound complex, it's better to try and make it work than just let the spread of disease continue

Results: Children younger than 15 years living in households that received handwashing promotion and plain soap had a 53% lower incidence of diarrhea (95% confidence interval [CI], –65% to –41%) compared with children living in control neighborhoods. Infants living in households that received handwashing promotion and plain soap had 39% fewer days with diarrhea (95% CI, –61% to –16%) vs infants living in control neighborhoods. Severely malnourished children (weight for age z score, <–3.0) younger than 5 years living in households that received handwashing promotion and plain soap had 42% fewer days with diarrhea (95% CI, –69% to –16%) vs severely malnourished children in the control group. Similar reductions in diarrhea were observed among children living in households receiving antibacterial soap.

http://jama.ama-assn.org/content/291/21/2547.full

Humans have been around for hundreds of thousands of years, but only within the last ten thousand have we been living in cities with population densities even close to that of Banupur (for instance). I'd reckon that these kinds of sanitation problems are actually very new to humanity, at least from a historical or evolutionary standpoint.

EDIT: This sound similar to the "autoimmune diseases and allergies are due to a lack of parasites and other bacteria" theory (or is it still a hypothesis?).