mireya villarreal is following this. >> reporter: amelia no longer allows her children to play in their yard. >> before my kids would play on the ground. grass. i didn't know i was harming my kids. >> reporter: her home sits a mile north of exide technologies, where according to these smokestacks were spewing dangerous levels of lead and arsenic particles into nearby communities for years. valleio's property tested positive at 1500 parts per million, above levels for hazardous waste by california state standards. several members of her family suffer from serious health conditions often associated with lead poisoning, including her five-year-old disabled son. >> i feel like my whole family's been taken advantage but yet we're not getting the proper help. it's taking quite a bit of time. ask once again, the damage has been done. >> reporter: since 1981, exide technologies recycled car batteries in vernon, california, using a temporary permit which allowed them to sidestep strict state hazardous waste laws for more than 30 years. during that time, the company was citeed by california's dep

mireya villarreal has more. it's new at noon. reporter: the fraternity notre dame mary of nazareth has been soon the sisters might be served with an addiction notice. the landlord is raising their monthly rent by more than 50%, from about $3500 to $5,500. >> we have no income. we don't get paid so we work for the four people. that is all -- poor people. >> from some donations and some of the things we are baking ourselves. we are ready -- we cannot make $2000 more a month. reporter: it is in the tenderloin neighborhood, once considered undesirable and now it within walking distance of a revitalized area. it's for twitter opens its headquarters in 2012. the demand for office faces skyrocketed citywide. >> it's an absolute frenzy. renton driven -- rants have manhattan. reporter: critics say san francisco's gentrification is affecting the city's character. >> prince of got too far into high into fast. if we start losing the nonprofits, either the arts, you lose the soul of your city. we cannot have that. reporter: the landlord says

mireya villarreal, cbs news, los angeles. >> axelrod: carnival is now under way in brazil, which is a huge draw, with at least one million tourists expected there to celebrate. and now a huge concern in the nation hit hardest by the zika virus. jon, a million tourists have come to brazil. a million will go home. so what does all this mean for the potential spread of the virus? >> reporter: well, jim, it's a great concern. because one theory about the way that zika actually came to brazil in the first place is that it was brought here in 2014 with the world cup soccer matches by someone who was infected with zika virus elsewhere, came to brazil, and then an uninfected mosquito here bit that person and got infected with the virus. now weg perhaps it could happen in reverse-- infected people here could then travel elsewhere and you would have local transmission in those countries. >> axelrod: scary scenario. so, jon, we learned a lot more about how zika is transmitted in terms of bodily fluids this week. what do we know now that we didn't before? >> reporter: it's been remarkable, jim. i

here's mireya villarreal. >> reporter: in the chaos and rubble, thousands of rescuers are working frant frantically and carefully for moments like this-- a baby pulled alive from a collapsed 17-story apartment building where dozens are believed still trapped. this woman says she jumped out of the window to survive, while another man says he barely made it out. "when i ran down from the third floor i found the whole second floor was gone," he says "and had to wait to be rescued by police." from the air, the except of the damage is clearly visible. collapsed, but the damage is especially evident on the ground, cars crushed, twisted metal everywhere. more than 500 now homeless. seismologists say the earthquake struck close to the surface, a large quake that shallow can be especially destructive. kate lao shaffner teaches flsh english in a town just south of the epicenter. >> reporter: the quake struck just as the taiwanese were preparing to celebrate one of their biggest holidays, the lunar new year. now it's a nation in mourning. it's mostly a grim task, but there's clear motivation not t

here's mireya villarreal. >> reporter: from the outside, lincoln high school does not look like a place that inspires greatness. old, with gates on the windows, in a tough east l.a. neighborhood. >> today is all about making your life easisi. >> reportete but look beyond all of that, and you'll find >> this is almost similar to this guy right here, right? >> reporter: the son of korean immigrants, yom teaches what is considered the hardest class in school, advanced placement calculus. >> one of my strategies, really to make sure to provide that environment where kids are not shamed of asking questions. do you get it? >> reporter: his approach to teaching goes beyond calculating the slope of a curve. yom makes his class meet after schools, on weekends, and even holidays. the hard work has paid off. >> it's not always fun, but i do know for sure, once they get the score and if i ask them, "hey, was it worth it?" every single one of them say it was so worth it. >> repepter: for three years in a row, every student that has walked into hislass has passed the a.p. calculus tt. and this year,

mireya villarreal has more on earthquakes. >> reporter: the ground keepss. shaking in oklahoma and more violently. this year already a 140 quakes, 3.0 or larger, an average of two and a half per day. before 2008 the average was one and a half per year. the small town of fairview iswn quickly gaining a big reputation for large quakes. it was the epicenter of yesterday's 5.1 and just last month a 4.8. >> just kind of rattled, rattled rattled and got stronger and stronger. >> reporter: geologist toddng halihan teaches at oklahoma state and believes water disposal wells used after hydraulic fracturing is linked to the quake increase. >> unfortunately we have a side effect that we are now generating seismicity due to the injection wells. these are pretty startling when you feel them.th there's now a lot of people experiencing them on a pretty broad scale.d sc >> homeowner kathy mathews says the state has mixed up its >> there is a greater impact on the economy when you have hundreds of millions of dollars worth of real estate that is being damaged by that activit

mireya villarreal, cbs news, los angeles. >> glor: new zealand was hit with an earthquake this morning, a magnitude 5.7 near the city of clieschurch. it did not do serious damage to buildings but it buckled roadways and caused some cliffs to collapse. >> up next a tremendous dunk and at the nba all-stars.ha clinically proven to help minimize blood sugar spikes. so you stay steady ahead. i've been blind since birth. i go through periods where it's hard to sleep at night, and stay awake during the day. learn about non-24 by calling 844-844-2424. or visit my24info.com. it's the little things in life that make me smile. spending the day with my niece. i don't use super poligrip for hold, because my dentures fit well. before those little pieces would get in between my dentures and my gum and it was uncomfortable. even well fitting dentures let in food particles. just a few dabs of super poligrip free is clinically proven to seal out more food particles so you're more comfortable and confident while you eat. so it's not about keeping my dentures in, it's about keeping the food particles out.